The Saint George's Night Uprising (1343–1345) was a large-scale revolt by the indigenous Estonian population in the Duchy of Estonia, the Bishopric of Ösel-Wiek, and territories controlled by the Teutonic Order. It aimed to overthrow the Danish and German rulers who had established dominance during the 13th-century Livonian Crusade and to eradicate the foreign-imposed Christian religion. The revolt began on April 23, 1343, with an attack on German and Danish nobility, leading to widespread destruction and the massacre of many Germans. Estonian rebels, after some initial victories, laid siege to Reval (Tallinn) and other strongholds.
However, the rebellion soon faltered. The Teutonic Order intervened and killed the four Estonian leaders under the guise of negotiations in Paide. This treachery marked the beginning of the collapse of the uprising. The Estonian forces suffered heavy defeats in the battles of Kanavere and Sõjamäe in May 1343. Meanwhile, attempts to gain support from Sweden and Russia failed.
In 1344, the Oeselians of Saaremaa rebelled against their German overlords, successfully holding off the Teutonic forces for a year. However, in 1345, the Teutonic Order returned, forcing the Oeselians to surrender. The rebellion ended with the final defeat of the Estonian forces, and in 1346, Denmark sold its Estonian territories to the Teutonic Order.
The uprising, although ultimately unsuccessful, marked one of the last major attempts by the native Estonian population to resist foreign domination. Afterward, Estonia remained under the control of the Teutonic Order and the Catholic Church, with the Estonian nobility disappearing and the population increasingly subjugated.