A military disaster is the defeat of one side in a battle or war which results in the complete failure of the losing side to achieve their objectives, often with a high and disproportionate loss of life. The causes are varied and include human error, inferior technology, logistical problems, underestimating the enemy, being outnumbered, and bad luck.Template:Sfn[1][2][3]
Entries on this list are those where multiple sources dealing with the subject of military disasters have deemed the event in question to be a military disaster (or an equivalent term).
Syracuse Expedition (415–413 BC).[6][7] A large force from Athens failed to conquer the city of Syracuse, weakening the Athenian military position and depriving the city of much-needed manpower.
Battle of Agincourt (1415).Template:Sfn[16]Script error: No such module "Unsubst". A large French army with a large contingent of knights was defeated by Henry V's much smaller army.
Spanish Armada (1588).Template:Sfn[16]Script error: No such module "Unsubst". An English fleet sent fire ships into the Spanish invasion fleet destroying some and scattering the rest effectively ending the invasion threat. The Armada would later run into storms and almost half the ships never returned to Spain, as well as more than half of the troops.
Charge of the Light Brigade (1854).[17][16]Script error: No such module "Unsubst". A British cavalry unit charged an active enemy artillery position due to miscommunication and suffered heavy casualties for no real advantage.
Battle of IsandlwanaTemplate:Sfn[7] (January 22, 1879). In the first major battle of the Anglo-Zulu War, a Zuluimpi overwhelmed and defeated two battalions armed with modern rifles and artillery. The battle was a major victory for the Zulus during the opening stages of the war.
Battle of StalingradTemplate:Sfn[16]Script error: No such module "Unsubst".[7] (winter of 1942–43). One of the turning points of World War II (European Theater). German General Friedrich Paulus failed to keep a mobile strategic reserve and the Sixth Army was surrounded by a rapid Soviet flanking attack. Rubble caused by German bombing and artillery fire left their tanks unable to enter the city. The 250,000+ German troops in Stalingrad surrendered despite Adolf Hitler’s promise that they would never leave the city.Script error: No such module "Unsubst".