View source for First Army (Bulgaria)

{{refimprove|date=March 2013}}
{{Infobox military unit
| unit_name                     = First Army
| image                         = 
| caption                       = 
| dates                         = 1912 – 1913 <br>1915 – 1918 <br>1941 – 1945 <br>1950 – 2015
| country                       = [[File:Flag of Bulgaria.svg|20px]] [[Kingdom of Bulgaria|Bulgaria]]
| allegiance                    = [[File:Flag of Bulgaria.svg|20px]] [[Bulgarian Army]]
| branch                        = 
| type                          = [[Field Army]]
| role                          = 
| size                          = 
| command_structure             = 
| current_commander             = 
| garrison                      = [[Sofia]]
| ceremonial_chief              = 
| colonel_of_the_regiment       = 
| nickname                      = 
| patron                        = 
| motto                         = 
| colors                        = 
| march                         = 
| mascot                        = 
|battles = {{Tree list}}
*[[Balkan Wars]]
**[[Battle of Kirk Kilisse]]
**[[Battle of Lule Burgas]]
**[[Chataldzha Line]]
**[[Battle of  Knjaževac]]
*[[First World War]]
**[[Serbian Campaign (World War I)|Serbian Campaign]]
**[[Macedonian front]]
*[[Second World War]]
**[[Operation Frühlingserwachen]]
**[[Nagykanizsa–Körmend offensive]]
**[[Vienna Offensive]]
{{tree list/end}}
| notable_commanders            = [[Vasil Kutinchev]]<br>[[Kliment Boyadzhiev]]<br>[[Vladimir Stoychev]]
| anniversaries                 = 
}}

The '''Bulgarian First Army''' was a [[Kingdom of Bulgaria|Bulgarian]] [[field army]] during the [[Balkan Wars]], [[World War I]] and [[World War II]].

==Balkan Wars==

===First Balkan War===
{{main|First Balkan War}}
Following the military reforms of 1907 the territory of the Bulgarian Kingdom was divided into three Army Inspectorates. Each of them was further divided into three division districts and in war time formed a field army.

The First Army was formed by the [[Army inspectorates of the Bulgarian Kingdom|First Army Inspectorate]], which had its headquarters in [[Sofia]] and controlled the First, Sixth and Seventh divisions. However, because of different circumstances the 7th and 6th divisions were detached from the First Army and replaced by the 3rd and newly formed 10th division, which were otherwise part of the Second Army Inspectorate. Thus after the declaration of general mobilization in September 1912 the army consisted of three infantry division and a cavalry regiment. However, only the 3rd division had its full wartime strength of three infantry brigades while the 10th division was formed by one brigade from the 1st division and another one from the 6th division. Hence it was called the "Mixed" division.

The order of battle on 4 of October 1912 [[Old Style and New Style dates|O.S.]] was as follows:

{| class="wikitable"
|+First Army Order of Battle<ref>''Войната между България и Турция, vol. II '', pag. 649–652,София 1928</ref>
!
!Battalions
!Men
!Rifles
!Machine guns
!Cannons
|-
|Army Staff and Services
|
|align="right"|1,439
|align="right"|424
|
|
|-
|First "Sofia" Infantry Division
|align="right" |17
|align="right"|24,976
|align="right"|17,885
|align="right"|16
|align="right"|60
|-
|Third "Balkan" Infantry Division
|align="right"|25
|align="right"|34,991
|align="right"|25,106
|align="right"|24
|align="right"|72
|-
|Tenth "Mixed" Infantry Division
|align="right"|17
|align="right"|23,693
|align="right"|17,269
|align="right"|16
|align="right"|48
|-
|Ninth Cavalry Regiment
|align="right"|
|align="right"|504
|align="right"|373
|align="right"|
|align="right"|
|-
|Supply Trains
|align="right"|
|align="right"|3,000
|align="right"|
|align="right"|
|align="right"|
|-
|'''Total'''
|align="right"|59
|align="right"|88,603
|align="right"|61,067
|align="right"|56
|align="right"|180
|}

The Bulgarian plan placed the First Army commanded by Lieutenant General [[Vasil Kutinchev]] in the center of the battle line and its task was to advance rapidly, engage the main Ottoman forces positioned between [[Kırklareli|Kirk Kilisse]] and [[Edirne|Adrianople]] and position itself so it could assist both the Second Army on the right flank and the Third Army on the left flank. To achieve this as soon as the advance began the 1st Brigade of the 3rd division was temporary assigned to the Second Army while the rest of the army advanced in the space between the two fortresses. In the ensuing [[Battle of Kirk Kilisse]], in which the Ottoman Eastern Army was defeated and retreated, the First Army bore the brunt of the fighting and suffered the greater part of the 5,745 Bulgarian casualties in that battle. The Bulgarian command ordered a couple of days' rest so that the forces can regroup before pursuing the enemy.

When the advance was renewed the First Army left behind the entire 3rd division around Adrianople to protect against attacks from the right flank. The Ottoman Army meanwhile had consolidated and reinforced itself on a new line from [[Battle of Lule Burgas|Lule Burgas to Bunar Hisar]]. The Bulgarians decided to carry out a frontal assault with the Third Army while the weakened First Army tried to enveloped the Ottoman left flank. This largest and bloodiest battle of the [[Balkan Wars]] the Bulgarians again emerged victorious and the Ottoman forces retreated in complete disorder. The heavy fighting inflicted around 20,000 casualties to the Bulgarian forces which again forced the Bulgarian command to order a couple of days' rest for the armies.

By the time the Bulgarians continued the advance the Ottoman Army had occupied the Chataldzha defensive line where it finally managed to hold its opponent after the battle on 4 and 5 November 1912.

The First and Third Bulgarian armies remained at the Chataldzha line until the end of the war and managed to repel several Ottoman attempted breakthroughs.

===Second Balkan War===
{{main|Second Balkan War}}
[[File:2nd-balkan-war-bulgarian-plan.JPG|thumb|265px|Initial Bulgarian plan of operations]]

In the aftermath of the [[First Balkan War]] the tensions between the allies grew significantly, as Bulgaria felt cheated out of its rightful share by Serbia and Greece.<ref>{{Cite news|url=http://www.history.com/this-day-in-history/the-first-balkan-war-ends|title=The First Balkan War ends - May 30, 1913 - HISTORY.com|work=HISTORY.com|access-date=2018-03-20}}</ref> After a surprise attack ordered by [[Ferdinand I of Bulgaria]], Serbia and Greece formed a new alliance directed against Bulgaria and the skirmishes between their troops and the much smaller Bulgarian forces that were left behind to protect their country's claims were becoming ever more frequent. In view of this situation the Bulgarian command began transferring its forces from [[East Thrace|Eastern Thrace]] to the western part of the country. During this time the organization of the field armies went through some major changes, including the creation of several new brigades and the formation of a new field army.

The First Army, still under the command of Lieutenant General [[Vasil Kutinchev]], was deployed in the northwestern part of the country between [[Vidin]] and [[Berkovitsa]], along the old border with [[Serbia]]. Its composition had changed significantly by 15 June 1913 and included two divisions, each with only two brigades, a few cavalry squadrons and an independent infantry brigade.

{| class="wikitable"
|+First Army Order of Battle<ref>''Кратък обзор на бойния състав, организацията, попълването и мобилизацията на българската армия '', pag. 92–93;Държавно военно издателство,София 1961</ref>
!
!Battalions<ref>А.Христов. ''Исторически преглед на войната на България срещу всички балкански държави '', pag. 35-34; Печатница на Армейския военно-издателски фронт,София 1922</ref>
!Men
!Rifles
!Cannons
|-
|Army Staff
|
|align="right"|713
|align="right"|
|
|-
|Fifth "Danube" Infantry Division
|align="right"|14
|align="right"|20,097
|align="right"|18,680
|align="right"|48
|-
|Ninth "Pleven" Infantry Division
|align="right"|16
|align="right"|26,740
|align="right"|22,284
|align="right"|32
|-
|Independеnt Brigade
|align="right"|8
|align="right"|9,139
|align="right"|5,782
|align="right"|28
|-
|'''Total'''
|align="right"|38
|align="right"|56,689
|align="right"|46,746
|align="right"|108
|}

The Bulgarians planned to begin the war with an offensive in which the First and [[Third Army (Bulgaria)|Third]] armies were to advance deep into [[Old Serbia]] and cut the communication and supply lines of the Serbian Army concentrated in [[Macedonia (region)|Macedonia]].

The conflict, however, began on 16 June 1913 when only the [[Fourth Army (Bulgaria)|Fourth]] and [[Second Army (Bulgaria)|Second]] armies were ordered to attack the Serbian and Greek armies. In the ensuing confusion for almost one week the remaining three Bulgarian armies received no orders to attack. It was only on the evening of 21 June when the First Army was ordered to advance against the town of [[Knjaževac]] and after it had occupied it to divide its forces in two with one part to be directed against [[Zaječar]] and the other one send to assist the Third army around [[Pirot]].

Facing the First Army was the Timok Army of 31 battalions and 12 gun batteries—mostly third line infantry, commanded by colonel Vukuman Arachich. The Bulgarians managed to defeat part of these forces and occupy Knjaževac while suffering only 280 men killed and 820 men wounded.

Meanwhile, Romania had declared war on Bulgaria and its army had begun invading the northern part of the country. This new enemy threatened the rear of the First Army and forced the Bulgarian high command to order its retreat back to the border.
That move had a very negative effect on the morale of the troops and even caused opened mutinies in the Ninth Division which became completely disorganized during the retreat. The situation was particularly bad in the division's Second Brigade which surrendered to the Romanian forces around [[Montana, Bulgaria|Montana]]. The rest of the Ninth managed to retreat to Sofia and later form the Samokov detachment which took an important part in the [[Battle of Kresna Gorge]]. The rest of the army also retreated towards [[Sofia]] and took defensive positions in the Balkan mountain passes. The Serbians took advantage of this and occupied [[Belogradchik]] where they established contact with the Romanian Army. Even though by now most of northwestern Bulgaria was lost, General Kutinchev kept a few battalions in the fortress of [[Vidin]] which managed to hold off all [[Siege of Vidin (1913)|Serbian attacks]] until the end of the war.

The Bulgarian high command now planned a decisive offensive operation against the Greek Army which was advancing in the Kresna Gorge. For that purpose Lieutenant General [[Vasil Kutinchev]] was assigned commander of the Second Army and the units of the First Army were transferred south to reinforce it.

A general armistice was concluded on 18 July 1913 and ten days later the [[Treaty of Bucharest (1913)|Treaty of Bucharest]], which stipulated immediate demobilization of the Bulgarian Army, was signed.

==First World War==

===Conquest of Serbia===

{{main|Serbian Campaign (World War I)|}}

With the outbreak of the [[First World War|Great War]] Bulgaria declared neutrality, as it still hadn't recovered from the losses suffered in the Balkan Wars. In 1915 activities in the diplomatic arena intensified and both the Entente and the Central powers tried to win new allies, especially in the [[Balkans]]. Bulgaria's main aim was to regain Macedonia but Serbia was unwilling to make any compromises which gave the German diplomacy a great advantage. The general military situation also favored the Central Powers—the Germans were holding firm on the [[Western Front (World War I)|Western Front]] and on the [[Eastern Front (World War I)|Eastern Front]] their [[Gorlice–Tarnów Offensive]] ended in major defeat for the Russians. Under these circumstances on 6 September (24 August) 1915 at the German military headquarters in [[Pszczyna|Pleß]] Bulgaria and Germany signed a [[Bulgaria–Germany treaty (1915)|treaty of alliance]]. A military convention, which included Austria-Hungary as a third party and laid the plan for the [[Serbian Campaign (World War I)|conquest of Serbia]], was also concluded.

In accordance with the convention Bulgaria began mobilizing and concentrating its forces its western border. For the campaign the Bulgarian high command planned to attack Serbia with two armies. The First Army under the command of Lieutenant General [[Kliment Boyadzhiev]] was deployed between the [[Danube]] and [[Tran, Bulgaria|Tran]]. As stipulated by the military convention it was part of [[Army Group Mackensen (Serbia)|Army Group Mackensen]] together with the German [[11th Army (German Empire)|Eleventh Army]] and the Austro-Hungarian Third Army.

On 1 October(14 October) 1915 the army had the following organization:

[[File:Bulgarian First Army 1915.JPG|thumb|350px|Advance of the army during the campaign]]

{| class="wikitable"
|+First Army composition <ref>''Българската армия в Световната война, vol. II '', pg. 892–905; Държавна печатница,София 1938</ref>
!
!Battalions
!Squadrons
!Men
!Rifles
!Machine guns
!Cannons
|-
|Army Staff and Services
|
|
|align="right"|2,165
|align="right"|593
|
|
|-
|First "Sofia" Infantry Division
|align="right"|23
|align="right"|1,5
|align="right"|44,270
|align="right"|25,921
|align="right"|24
|align="right"|111
|-
|First Cavalry Brigade
|align="right"|3
|align="right"|8
|align="right"|6,204
|align="right"|3966
|align="right"|8
|align="right"|30
|-
|Sixth "Bdin" Infantry Division
|align="right"|23
|align="right"|5,5
|align="right"|48,022
|align="right"|26,887
|align="right"|28
|align="right"|119
|-
|Eight "Tundzha" Infantry Division
|align="right"|23
|align="right"|1,5
|align="right"|45,978
|align="right"|27,146
|align="right"|24
|align="right"|88
|-
|Ninth "Pleven" Infantry Division
|align="right"|23
|align="right"|1,5
|align="right"|44,712
|align="right"|27,832
|align="right"|24
|align="right"|74
|-
|Border Guards
|align="right"|4
|align="right"|
|align="right"|4,269
|align="right"|4224
|align="right"|
|align="right"|
|-
|'''Total'''
|align="right"|99
|align="right"|18
|align="right"|195,620
|align="right"|116,569
|align="right"|108
|align="right"|422
|}

The Serbians were informed about the Bulgarian war preparations by their military attaché in [[Sofia]] and the units covering the border between the two countries. Once Bulgaria declared mobilization the Serbian High Command planned a preemptive strike against the Bulgarian forces who were still concentrating and organizing on the border. For that purpose it deployed the entire [[Second Army (Serbia)|Second Army]], the Timok Army, the Kraina detachment and the Vlasinski detachment against the sector of the Bulgarian First Army. These were sizable forces of around 100 battalions with 90,000 rifleman, 248 cannons and 94 machine guns.<ref>''Българската армия в Световната война, vol. II '', page 5; Държавна печатница,София 1938</ref> In addition the Serbians also had a [[Greek–Serbian Alliance of 1913|defensive alliance]] with Greece and hoped the Greek Army would also intervene. The Serbs have also asked the Entente for assistance in the form of a 150,000 strong army. Although the Entente couldn't provide the troops the Serbian army was prepared to attack Bulgaria. However, the Serb Prime Minister Pašić did not dare to attack Bulgaria over explicit opposition of all the Allied Powers (Russia, France and Great Britain).

On 1 October(14 October) 1915 Bulgaria declared war on Serbia and the First Army was ordered to begin its [[Morava Offensive]]. Its primary objectives were to push the Serbian forces out of the [[Timok (river)|Timok]] and [[Great Morava|Morava]] valleys, to link up with Austro-Hungarian forces advancing from [[Orșova]] and secure the Belgrade—Sofia railway by capturing [[Niš]], war-time capital of Serbia.

The Bulgarian Army crossed the border on October 11.<ref>The encyclopedia Americana, Volume 29, page 307</ref> But the first two weeks of the offensive the advance was slow as the divisions of the army operated independently towards achieving their individual objectives. In the southern sector the "Sofia" infantry division was engaged in heavy fighting with parts of the Serbian Second Army and failed to take [[Pirot]]. However, the Bulgarian advance in the north was proceeding more rapidly and the taking of [[Knjaževac]] by the "Tundzha" division eventually forced the Serbians to pull out of [[Pirot]] in order to avoid encirclement. This was a minor success for the Bulgarians which captured 14 cannons and c. 1,500 prisoners but the main Serbian forces were allowed to retreat in good order.

Faced with the war on several fronts the Serbian High Command decided that it is best for the army to try to hold its opponents for as long as possible and retreat slowly to the south, southwest until help arrived from the Allies who had landed in [[Thessaloniki]]. Under these circumstances the renewed drive of the Bulgarian Army faced determined resistance but it was not enough to prevent the fall of [[Aleksinac]] and on 23 October (5 November) 1915 the 9th "Pleven" division entered Niš where the Serbians had left some 42 old fortress cannons, several thousand rifles and a big amount of ammunitions, in addition around 5,000 soldiers surrendered or were captured by the Bulgarians. The Belgrade–Sofia railway was now opened for the Central Powers and a permanent land connection was established. The Serbians, however, managed to destroy the bridges of the [[Great Morava|Morava]] river and slowed significantly the Bulgarian First Army which spend the time between 24 and 31 October in unsuccessful attempts to cross the river. This marked the end of the Morava Offensive.

Having suffered heavy losses the Serbian Army retreated towards [[Kosovo]] where they prepared to make their last stand. The Central Powers meanwhile prepared a plan to encircle the Serbian forces. The Bulgarian High Command and the headquarters of Army Group "Mackensen" agreed to pursue relentlessly the retreating opponent, to cut its possible retreat routes through Macedonia and to undertake a decisive advance towards [[Pristina]] and prevent a Serbian retreat to the west. The plan required the Bulgarian First Army to attack from the east, a detached part of the Second Bulgarian Army from the South, the [[11th Army (German Empire)|Eleventh army]] from the north and finally the main forces of the Third Army from the northwest while its XIX Army Corps blocks any Serbian retreat to the west. However, after the fall of [[Niš]] the Germans began pulling out some of their forces from the [[Balkans]] and the Bulgarian Sixth and Ninth divisions had been slowed by the swollen waters of the [[Great Morava|Morava]] and the destruction of its bridges. In these circumstances on 1 November the Central Powers began the [[Kosovo Offensive (1915)|Kosovo Offensive]].

Contrary to the intentions of [[generalfeldmarschall]] Mackensen the advance of his army group proved to be difficult and slow due to bad roads, lack of supplies and the cold weather. This allowed the Serbians to gradually retreat in good order further into [[Kosovo]] and to concentrate greater forces against the Northern Operations Group of the Second Bulgarian Army in an attempt to break through and join the French and British forces advancing up the [[Vardar]] valley. In view of these events on 6 November the 8th "Tundzha" division left the First Army and was placed under the command of the Northern Operations Group while the 6th "Bdin" division was ordered to redeploy around [[Blagoevgrad]] and [[Dupnitsa]] under the direct control of the Bulgarian high command. The exhausted Serbians failed to achieve their aims and in the face of the continued advance of the Bulgarian forces towards [[Pristina]] from the east and the south ordered a general withdrawal . On 10 November the 9th "Pleven" division and the German [[101st Infantry Division (German Empire)|101st division]] entered the town but the successful retreat of the Serbian Army on the right bank of the river [[Sitnica]] meant that its attempted encirclement had failed. This ended the second phase of the campaign.

After the defeat in [[Kosovo]] the remnants of the Serbian Army began its retreat through [[Albania]] to the Adriatic coast. The Germans thought that the campaign was over and continued pulling out their troops from the front while the pursuit of the retreating opponent was left mostly to Bulgarian and Austro-Hungarian forces. On 24 November the 3rd "Balkan" division took [[Prizren]] and was placed under the command of the First Army. With the end of the campaign a general order for the regrouping of all Bulgarian forces was issued. The 9th division was moved to the [[Skopje]]-[[Prilep]] area, the 1st "Sofia" division was ordered to concentrate around [[Kratovo, Macedonia|Kratovo]], where it would remain under the direct control of the Bulgarian high command. The cavalry division and the 8th "Tunzha" infantry division were also ordered to join the First Army.

===Macedonian Front===

{{main|Macedonian Front (World War I)|}}

<!-- Deleted image removed: [[File:Generla boyadziev s shtaba na 1va armija.jpg|thumb|350px|eight|General Boyadzhiev and his staff officers in Macedonia.]] -->
With the successful conclusion of the Serbian campaign and withdrawal of the French and British expeditionary forces back to [[Thessaloniki|Salonika]] the Bulgarian armies reached the Greek border. Under the influence of the German high command they were ordered not to cross into Greek territory. The Bulgarian commander-in-chief general [[Nikola Zhekov]] remained concerned about the increasing Allied presence in Greece and insisted upon an attack on Salonika. Instead on 9 February 1916 during a meeting in the German military headquarters in [[Pszczyna|Pleß]] he and the Chief of the General Staff [[Erich von Falkenhayn|von Falkenhayn]] agreed to begin fortifying the positions that were already taken on the Greek border and to resolve the question of an offensive latter.

Since December 1915 the Bulgarian First Army consisted of the 8th, 9th and 3rd infantry divisions and the cavalry divisions and occupied a 140-kilometer front, from [[Debar]] and [[Struga]] to the bend of the river [[Crna River (Vardar)|Cherna]] and the [[Vardar]]. It remained part of Army Group "Mackensen", which had its headquarters in [[Skopje]], together with the Bulgarian 5th "Danube" division, the German 4th Reserve Corps and the German 210th composite brigade which formed the [[11th Army (German Empire)|Eleventh Army]].

In the spring of 1916 as the Allies had finished fortifying the area around Salonica and it became obvious that no Bulgarian and German offensive was going to take place, the French and British forces moved up to the Greek border where they established contact with the Bulgarian forces. In the beginning of April the positions of the Eleventh Army were subjected to heavy artillery shelling and field marshal Mackensen requested the 9th "Pleven" infantry division to be given to that army so that it can consolidate its position. General [[Nikola Zhekov|Zhekov]] agreed and ordered the division to leave the First Army, join the Eleventh Army and concentrate behind the German 4th Corps.

By 1 June the Entente forces were additionally strengthened by the arrival of some 115,488 Serbian soldiers, which were organized in three corps-sized formations called armies. The Allies now had over 313,000 troops in the theater which increased the Bulgarian concerns. By July [[Romania]] was preparing to enter the war on the side of the [[Triple Entente|Entente]] which placed Bulgaria in a difficult position facing a possible war on two fronts and in the beginning of August the French and British launched an offensive against the Bulgarian positions at [[Battle of Doiran (1916)|Lake Dojran]] which convinced the Bulgarian high command that the Allies were preparing a general offensive. To counter these negative developments the Bulgarians planned an offensive of their own with both their flanks aiming to shorten the front line and influence Romania in its decision to enter the war.

The advance on the right flank was to be undertaken by the Bulgarian First Army which had the following order of battle in July 1916:

{| class="wikitable"
|+First Army Order of Battle<ref>Петър Дошкинов. ''Чеганската операция. Книга 2'', pagе 115–117;Печатница на военно-издателския фонд,София 1940</ref>
!
!Battalions
!Men
!Rifles
!Machine guns
!Cannons
|-
|Army Staff, rear services etc.
|
|align="right"|13,361
|align="right"|5,524
|
|
|-
|Eighth "Tundzha" Infantry Division
|align="right"|22
|align="right"|41,376
|align="right"|22,538
|align="right"|36
|align="right"|48
|-
|3/6 Infantry Brigade
|align="right"|10
|align="right"|8,029
|align="right"|6,491
|align="right"|12
|align="right"|12
|-
|Third Cavalry Brigade
|align="right"|
|align="right"|1,892
|align="right"|1,310
|align="right"|
|align="right"|4
|-
|Third "Balkan" Infantry Division
|align="right"|21
|align="right"|42,777
|align="right"|26,953
|align="right"|36
|align="right"|48
|-
|Army Units (15th IR, reserves etc.)
|align="right"|4
|align="right"|7,946
|align="right"|7,000
|align="right"|20
|align="right"|66
|-
|German Units
|align="right"|
|align="right"|1,987
|align="right"|987
|align="right"|24
|align="right"|12
|-
|'''Total'''
|align="right"|57
|align="right"|117,368
|align="right"|70,803
|align="right"|128
|align="right"|190
|}

The Germans finally agreed that an offensive was needed and on 12 August general Boyadzhiev received his orders from the headquarters of [[Army Group Mackensen (Serbia)|Army Group "Mackensen"]]. The right wing of the army, consisting of the reinforced 8th infantry division (four and half infantry brigades) was to advance and take [[Florina]] while parts of the 3rd division towards the Chegan mountain range and the village of the same name. General Boyadzhiev agreed to attack but had concerns regarding the final results of the offensive because his army was scattered on a 140&nbsp;km front and lacked enough mountain and heavy artillery.
Facing the Bulgarians were the six infantry and one cavalry divisions of the three Serbian armies.

The offensive began on 17 August 1916 with the Bulgarians taking Florina (Lerin), [[Vevi|Banitsa]] and [[Kastoria]]. The advance, however, soon ran into difficulty and slowed down considerably due to the increased Serbian resistance. The fighting was especially heavy on the bare rocky slopes of the Chegan Mountain and the [[Voras Mountains|Nidže]]. The Serbians were constantly reinforced with new artillery and fresh troops thanks to railway that reached the battlefield while the Bulgarians soon began depleting their ammunition stocks. This and the slow advance forced the Bulgarian high command to call off all attacks on 27 August and order the forces to dig in on the occupied positions between [[Vegoritida|Lake Ostrovo]], [[Limni Petron|Lake Petrovsko]] and along the ridges of the Nidže. For the next several days the Bulgarian positions were subjected to heavy artillery fire and few Serbian attacks that were repulsed. The so-called [[Battle of Florina|Chegan Offensive]], also known as the Lerin Offensive, had failed. It failed to influence [[Kingdom of Romania|Romania]], which [[Romania in World War I|entered the war]] on the side of the Allies but also failed to achieve its final military objective to take the Chegan village and the pass north of Lake Ostrovo.

General [[Maurice Sarrail]] now prepared a counterattack against the First Bulgarian Army that would eventually develop in the [[Monastir Offensive]]. The blow was to be directed against the right wing of the First Army which consisted of the Third infantry brigade of the 6th "Bdin" division, the Third cavalry brigade and the 8th "Tundzha" and First infantry brigade of the Third "Balkan" infantry division or in total about 36 infantry battalions, 74 machine guns and 35 artillery batteries. Against them were arrayed the Serbian [[Third Army (Serbia)|Third Army]] and the divisional group of general Cordonnier.

The offensive began with the [[battle of Malka Nidzhe]] on 12 September 1916. After two days of fighting the Serbians achieved a breakthrough around [[Kelli, Florina|Gornichevo]] and forced the Bulgarian 8th division to retreat. Meanwhile, the [[Battle of Kaymakchalan|battle for Kajmakcalan]] also began. The fall of Florina on 23 September and the retreat of the Bulgarian First Army forced some changes in the [[Central Powers]] command structure. On 27 September general [[Kliment Boyadzhiev]] was replaced as commander of the First Army by general [[Dimitar Geshov]]. The Army itself exchanged headquarters with the [[11th Army (German Empire)|Eleventh Army]], now under the command of general [[Arnold von Winckler]], and came under the new Army Group "[[Otto von Below|Below]]", replacing Army Group "Mackensen" which was dissolved on the Macedonian Front on 30 July 1916 as field marshal Mackensen was needed in northern Bulgaria to take command of the forces concentrating for the operations against Romania. The former units of the First Army, now under German command, continued fighting around [[Bitola|Monastir]] till December when the Allied offensive was finally halted.

The new Bulgarian First Army now consisted of the Fifth "Danube" Infantry Division on the western bank of the [[Vardar]], the Ninth "Pleven" Infantry Division between the Vardar and [[Doiran Lake|Lake Dojran]], one brigade from the Eleventh "Macedonian" Infantry Division from Lake Dojran to the [[Belasica]] Mountain. For the rest of 1916 its sector saw only secondary fighting.

On 21 April 1917 general [[Otto von Below]] was called to the [[Western Front (World War I)|Western Front]] and was replaced by general [[Friedrich von Scholtz]] who established a new army group bearing his name and composed of the Eleventh and First armies.
During that time general [[Maurice Sarrail]] attempted a new offensive aiming to break the [[Macedonian front]]. The British were the first to attack the Ninth "Pleven" Division around Lake Dojran on 22 April. They were followed by the Serbians and the French who attack through the [[Crna River (Vardar)|Cherna Loop]] in May. This offensive, however, proved a big disappointment as the French who took the Yarebichina peak from the Fifth "Danube" Division were driven back by the Bulgarians and the British suffered a heavy defeat in the [[Battle of Doiran (1917)|Second Battle of Dojran]]. By 23 May the offensive was cancelled and the Allies began fortifying their positions in expectation of a Bulgarian counter-offensive which never came. Then for a period of almost one year there were only a few local actions along the entire front.

By 1918 the Bulgarian positions in Macedonia had deteriorated drastically as the morale of the forces decreased due to lack of supplies and ammunition. Then in May the positions of the First Army in the sector of the Fifth Division were attacked by the Greek Army, which had [[Greece during World War I|officially joined the Allied forces]] in 1917. In the ensuing [[Battle of Skra-di-Legen]] at the peak of Yarebichina the Bulgarians lost almost their entire 49th Infantry Regiment. This victory was of little strategic value to the Allies but it sapped the [[morale]] of the Bulgarian troops in the sector. After the battle general [[Nikola Zhekov]], general Sholtz and [[crown prince]] [[Boris III of Bulgaria|Boris]] arrived at the headquarters of the Fifth Division to inquire for the causes of the defeat. They reinforced the division with the 80th infantry regiment and planned a demonstrative attack along the [[Struma (river)|Struma]] by the [[Second Army (Bulgaria)|Second Army]] in order to retake the heights. The plan, however, never went into action as the morale of the forces in the Fifth Division was so low that an attack was impossible. General Zhekov then sought to remedy the situations by replacing the commander of the First Army general [[Dimitar Geshov]] with the former commander of the Ninth "Pleven" Division general [[Stefan Nerezov]].

Morale in some parts of the front, however, remained critical as news about German misfortunes in the Western Front reached the troops on the [[Balkans]] the few remaining German troops in Macedonia were being pulled out and the deprivations in the Bulgarian Army continued. The new commander of the Allied Salonica forces [[Louis Franchet d'Espèrey|Franchet d'Espèrey]] planned to take advantage of this by organizing a new great offensive in Macedonia. For that purpose he gathered a force of 28 divisions or between 670,000 and 717,000 men with over 2,000 artillery pieces, 2609 machine guns and 200 airplanes. The main blow was to be delivered against the German Eleventh Army, which by now consisted almost entirely by Bulgarian units at Dobro Pole, with secondary attacks to the west around [[Bitola]] and to the east against the Bulgarian First Army at Lake Doiran .

In September 1918 the First Army had the following order of battle:

{| class="wikitable"
|+First Army Order of Battle<ref>Стефан Нойков. ''Защо не победихме'', pagе 148;Печатница на Армейския военно-издателския фонд,София 1922</ref>
!
!Front line in km
!Battalions
!Machine guns
!Cannons
!Mine throwers
|-
|Fifth "Danube" Infantry Division
|align="right"|25
|align="right"|24
|align="right"|267
|align="right"|188
|align="right"|53
|-
|Mountain Division
|align="right"|19
|align="right"|9
|align="right"|92
|align="right"|69
|align="right"|16
|-
|Ninth "Pleven" Infantry Division
|align="right"|10
|align="right"|17
|align="right"|184
|align="right"|119
|align="right"|34
|-
|1/11 Infantry Brigade
|align="right"|12
|align="right"|6
|align="right"|64
|align="right"|24
|align="right"|
|-
|Army Reserve
|align="right"|
|align="right"|7
|align="right"|56
|align="right"|
|align="right"|
|-
|'''Total'''
|align="right"|57
|align="right"|63
|align="right"|663
|align="right"|400
|align="right"|103
|}

For the operations against the Bulgarian First Army the Allied command designated the forces of general [[George Milne, 1st Baron Milne|Milne]]. Those consisted of 4 British and 2 Greek infantry divisions or about 66 battalions with 300 artillery pieces and 400 machine guns. General Milne decided to deliver his main blow against the 9th Division while a secondary attack was planned against the 1st brigade of the 11th Infantry Division.

The Allied [[Vardar Offensive]] opened on 15 September 1918 with the [[Battle of Dobro Pole]] and after a relative short struggle a breakthrough was achieved. On the next day at Lake Doiran the Allies began a two-day artillery [[Barrage (artillery)|barrage]] in which more than 300,000 ordinary and gas shells were fired on the Bulgarian positions. Unlike at Dobro Pole, however, the troops in the Doiran sector preserved their high morale due to the personal inspection of the battlefield that the army commander general Nerezov made and the skilful leadership of the commander of the division general [[Vladimir Vazov]]. In addition the two commanders had regrouped their forces in such a way that a sufficient reserve of two regiments was immediately available. The modern and well build fortifications also made the casualties from the barrage extremely low. So when the Allied infantry began advancing the Bulgarians were ready to meet them with all their available forces. The result was a two-day bloody battle in which the British and Greeks suffered a heavy defeat. In fact the victory was so encouraging that general Nerezov was preparing for a counter-attack with his army supported by the neighboring [[Second Army (Bulgaria)|Second Army]] which until now had remained completely inactive. In addition he could also rely on the [[Fourth Army (Bulgaria)|Fourth Army]], further down the Struma. In this decisive moment on 19 September the acting commander-in-chief general [[Georgi Todorov (general)|Georgi Todorov]] met with general [[Friedrich von Scholtz]] to decide what to do. The question of a counter offensive with the right wing of the Eleventh Army and the Bulgarian First Army was put forward but was quickly dismissed by the Germans as impossible. In addition no real reinforcements from them were going to arrive on time. During this period of hesitation the danger to the right flank of the First Army grew and it was finally ordered to retreat. The defeated British took advantage of this and began pursuing. In the next several days the situation deteriorated and several thousand Bulgarian soldiers revolted and headed towards [[Sofia]] and on 27 September they proclaimed the overthrow of the monarchy. During this time the Bulgarian government was under pressure from all sides and finally decided to begin negotiations so on 29 September the [[Armistice of Salonica|Salonica Armistice]] was concluded. The First Army was demobilized on 15 October 1918.

===Commanders===

<gallery class="center">
Image:General Kliment Bojadzijev.jpg|Lt. Gen. [[Kliment Boyadzhiev|Boyadzhiev]]<br>(11.09.1915 – 25.09.1916)
Image:General Dimitar Geshov.jpg|Lt. Gen.[[Dimitar Geshov|Geshov]]<br>(25.09.1916 – 30.07.1918)
Image:Stefan Nerezov.JPG|Lt. Gen. [[Stefan Nerezov|Nerezov]]<br>(30.07.1918 – 15.10.1918)
</gallery>

==Second World War==

===World War II for the Axis===
{{main|Military history of Bulgaria during World War II}}
The [[Kingdom of Bulgaria]], under [[Tsar]] [[Boris III of Bulgaria|Boris III]], aligned itself with [[Adolf Hitler]]'s [[Nazi Germany]], and as a result regained [[Southern Dobruja]] in the [[Treaty of Craiova]] of September 1940, and occupied [[Western Thrace]], and much of [[Macedonia (region)|Macedonia]] after the Germans [[Invasion of Yugoslavia|invaded Yugoslavia]] and [[Battle of Greece|Greece]] in April 1941. In the [[Bulgarian Army]], there were four or five field armies, including the First Army, and some 30 divisions. On 22 June 1941, the First Army included the [[1st Division (Bulgaria)|1st Division]]; the [[7th Division (Bulgaria)|7th Division]] ([[:bg:Седма_пехотна_рилска_дивизия]]); two border guard regiments, a machine-gun battalion, other artillery units, engineers, and other supporting units.<ref>Leo Niehorster, [http://niehorster.org/032_bulgaria/1941_oob/corps_01.html I Army Corps "First Army"]</ref>

In the spring of 1942, Hitler requested Boris' help controlling [[Territory of the Military Commander in Serbia|occupied Serbia]]. The Tsar allowed the Germans to use his First Army, and so the First Army began its occupation duty in [[Yugoslavia]], where the [[Yugoslav Partisans|partisan movement]] was already active.

===World War II for the Allies===
In early September 1944, the rapidly advancing [[Red Army]] [[Second Jassy–Kishinev Offensive|reached the northern border]] of Bulgaria. The Bulgarians continued fighting the guerrillas in Thrace and Macedonia, but also turned their guns on the [[Nazi Germany|Germans]]. By the end of the month the First Army, together with the Bulgarian [[Second Army (Bulgaria)|Second]] and [[Bulgarian Fourth Army|Fourth]] Armies, was in full-scale combat against the [[German Army (1935–1945)|German Army]] along the Bulgarian-Yugoslav border, with Yugoslav guerrillas on their left flank and a [[Soviet Union|Soviet]] force on their right. At this time the First Army consisted of three 10,000-men divisions.

By December 1944, the First Army numbered 99,662 men. The First Army took part in the Bulgarian Army's advance northwards into the [[Balkans|Balkan Peninsula]] with logistical support and under command of the Red Army. The First Army, along with the rest of the Bulgarian forces, advanced into [[Hungary]] and [[Austria]] in the spring of 1945, despite heavy casualties and bad conditions in the winter. Because of the army's equipment shortages, on March 14, 1945, the Soviets agreed to provide the Bulgarians 344 aircraft, 65 T-34 tanks, 410 guns, 115 anti-aircraft guns, 370 mortars, 370 transport vehicles, and some 30,000 small arms, all free of charge.<ref>Gosztony, p. 211.</ref>

During 1944–45, the Bulgarian First Army was commanded by Lieutenant-General [[Vladimir Stoychev]]. On 8 May 1945, Gen. Stoychev signed a demarcation agreement with [[United Kingdom|British]] V Corps commander [[Charles Keightley]] in [[Klagenfurt]], southern [[Austria]].

== Cold War ==
From 1950, the army was stationed in Sofia. During the [[Cold War]] it was reestablished, and it covered mainly the southwestern direction, opposing the [[Greek Army]]. The [[Third Army (Bulgaria)|3rd Army]] with headquarters in Sliven opposed the [[Turkish Land Forces]]' [[First Army (Turkey)|First Army]], and the Bulgarian 2nd Army with its headquarters in Plovdiv was planned to support the 1st and 3rd Armies).

In 1988 the army included the:<ref>{{cite web|author=Michael Holm|title=1st Army – 1-ва армия – Military Unit: 22490|url=http://www.ww2.dk/new/wp/Bulgaria/1a.htm|date=2015}}</ref>
*[[1st Motor Rifle Division (Bulgaria)]] (Slivnitsa, Bulgaria)
*[[3rd Motor Rifle Division (Bulgaria)]] (Blagoevgrad, Bulgaria)
*[[21st Motorised Rifle Division (Bulgaria)]] (Pazardzhik, Bulgaria)
*[[9th Tank Brigade (Bulgaria)]] ([[Gorna Banya]], Bulgaria)
*46th Missile Brigade (Samokov, Bulgaria)
*5th Army Artillery Regiment (Samokov, Bulgaria)
*35th Army Anti-Tank Artillery Regiment (Samoranovo, Bulgaria)
*1st Army Anti-Aircraft Artillery Regiment

Other smaller units included the 88th Army Engineer Regiment (Kyustendil, Bulgaria); the 4th Army Communications Regiment (Sofia); the 38th Army Chemical Defence Battalion (Musachevo, Bulgaria); the 1st Cable-Layer Communications Battalion (Sofia); the 1st independent Electronic Warfare Battalion (Sofia); and the 1st Army Parachute Reconnaissance Battalion (Gorna Banya).

During a series of reforms following the dissolution of the Warsaw Pact and the end of the Cold War, the 1st Army was reformed into the 1st Army Corps, later into the West Command, comprising mainly the [[9th Mechanized Brigade (Bulgaria)]] (in [[Gorna Banya]]) and mobilization units. With the adoption of Plan 2004 and Plan 2015 for organizational development of the Bulgarian Army forces, the command was first disbanded, later the 9th Mechanized Brigade was reformed into a brigade command with two mechanized battalions (in Gorna Banya and Blagoevgrad), and finally the brigade command was disbanded as the last successor unit of the 1st Bulgarian Army.

==Commanders ==
*Major General (Lieutenant General of August 2, 1912) [[Vasil Kutinchev]] (1912–1913)
*Lieutenant General [[Kliment Boyadzhiev]] (October 1915 – September 11, 1916)
*Major General (Lieutenant General of May 20, 1917) [[Dimitar Geshov]] (September 11, 1916 – December 1917)
*Major General (Lieutenant General of August 15, 1917) [[Stefan Nerezov]] (July 30 / October 16, 1918 – 1920)
*Colonel Rashko Atanasov (1931)
*Lieutenant-General Konstantin Solarov (since 1931)
*Lieutenant-General [[Nikola Mikhov]] (August 11, 1941 – April 11, 1942)
*Major General (Lieutenant General of May 6, 1944) [[Nikola Nakov]] (April 11, 1942 – September 13, 1944)
*Colonel (Major General of October 3, 1944, Lieutenant General of October 18, 1944) [[Vladimir Stoychev]] (September 13, 1944 – November 21, 1945)

==See also==
*[[Operation Spring Awakening]]
*[[Battle of the Transdanubian Hills]]
*[[Nagykanizsa–Körmend Offensive]]
*[[Second Army (Bulgaria)|Second Army]]
*[[Third Army (Bulgaria)|Third Army]]
*[[Fourth Army (Bulgaria)|Fourth Army]]
*[[11th Macedonian Infantry Division]]

==Footnotes==
{{reflist}}

==References==
* {{cite book |title=The Balkan Wars, 1912–1913: Prelude to the First World War |last=Hall |first=Richard C. |year=2000 |publisher=Routledge |isbn=0-415-22946-4 | url=https://books.google.com/books?id=ZSllgZ-1D4YC }}
* {{cite book |title=Defeat in Detail: The Ottoman Army in the Balkans, 1912–1913 |last=Erickson |first=Edward J. |year=2003 |publisher=Greenwood Publishing Group |isbn=0-275-97888-5 | url=https://books.google.com/books?id=3fYuy5iUi_sC}}
*{{cite book|last=Hall | first=Richard | title=Balkan Breakthrough: The Battle of Dobro Pole 1918 | publisher=Indiana University Press | year= 2010 | isbn= 978-0-253-35452-5}}
* Gosztony, Peter. ''Stalins Fremde Heere''. Bonn: Bernard & Graefe Verlag, 1991. {{ISBN|3-7637-5889-5}}.
* {{cite book| last = Mollo| first = Andrew| title = The Armed Forces of World War II| publisher =Crown| year = 1981| location = New York | isbn = 0-517-54478-4}}
* Ready, J. Lee. ''World War Two Nation by Nation''. London: Arms and Armour Press, 1995.
* Thomas, Nigel, and, Mikulan, Krunoslav. ''Axis Forces in Yugoslavia 1941–45''. Oxford and New York: Osprey, 1995. {{ISBN|1-85532-473-3}}.
* Щаб на войската. "Българската армия в Световната война, vol. II"; Държавна печатница,София 1938
* Щаб на войската. "Българската армия в Световната война, vol. IV"; Държавна печатница,София 1940
* Петър Дошкинов. ''Чеганската операция. Книга 2''. Печатница на военно-издателския фонд,София 1940

{{Bulgaria in World War I}}

[[Category:Military units and formations of the Balkan Wars]]
[[Category:Field armies of World War I]]
[[Category:Military history of Bulgaria during World War II]]
[[Category:Military units and formations of Bulgaria in World War II]]
[[Category:Field armies of Bulgaria|01]]
[[Category:Military units and formations established in 1912]]
[[Category:Military units and formations disestablished in 1913]]
[[Category:Military units and formations established in 1915]]
[[Category:Military units and formations disestablished in 1918]]
[[Category:Military units and formations established in 1941]]
[[Category:Military units and formations disestablished in 1945]]