Livonia is a historical region on the eastern shores of the Baltic Sea. It is named after the Livonians, who lived on the shores of present-day Latvia.

By the end of the 13th century, the name was extended to most of present-day Estonia and Latvia that had been conquered during the Livonian Crusade (1193–1290) by the Livonian Brothers of the Sword. Medieval Livonia, or Terra Mariana, reached its greatest extent after Saint George's Night Uprising that in 1346 forced Denmark to sell the Duchy of Estonia (northern Estonia conquered by Denmark in the 13th century) to the State of the Teutonic Order. Livonia, as understood after the retreat of Denmark in 1346, bordered on the Gulf of Finland in the north, Lake Peipus and Russia to the east, and Lithuania to the south.

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