The State of the Teutonic Order (German: Staat des Deutschen Ordens, pronounced [ˈʃtaːt dɛs ˌdɔʏtʃn̩ ˈʔɔʁdn̩s] ) was a theocratic state located along the southeastern shore of the Baltic Sea in northern Europe. It was formed by the knights of the Teutonic Order during the early 13th century Northern Crusades in the region of Prussia. In 1237, the Livonian Brothers of the Sword merged with the Teutonic Order of Prussia and became known as its branch – the Livonian Order (while their state, Terra Mariana, covering present-day Estonia, Latvia, and a small part of Russia, became part of the State of the Teutonic Order). At its greatest territorial extent during the early 15th century, the State encompassed Chełmno Land, Courland, Gotland, Livonia, Estonia, Neumark, Pomerelia (Gdańsk Pomerania), Prussia and Samogitia.
Following the battles of Grunwald in 1410 and Wilkomierz in 1435, the State fell into decline. After losing extensive territories in the imposed Peace of Thorn in 1466, the extant territory of its Prussian branch became known as Monastic Prussia (Polish: Prusy zakonne) or Teutonic Prussia (Polish: Prusy krzyżackie). It existed until 1525 as a fiefdom of the Polish Crown. The Livonian branch joined the Livonian Confederation and continued to exist as part of it until 1561.