The State of the Teutonic Order () was a medieval Crusader state, located in Central Europe along the southeastern shore of the Baltic Sea. It was formed by the knights of the Teutonic Order during the 13th century Northern Crusades in the region of Prussia. The Livonian Brothers of the Sword merged in 1237 with the Teutonic Order of Prussia and became known as its branch, the Livonian Order, while their state,Terra Mariana, became a part of the State of the Teutonic Order. At its greatest territorial extent, in the early 15th century, it encompassed Chełmno Land, Courland, Gotland, Livonia, Neumark, Pomerelia (Gdańsk Pomerania), Prussia and Samogitia, i.e. territories nowadays located in Estonia, Latvia, Lithuania, Germany, Poland, Russia, and Sweden.
Following the battles of Grunwald in 1410 and Wilkomierz in 1435, the State fell into decline. After losing extensive territory in the imposed Peace of Thorn in 1466, the extant territory of its Prussian branch became known as Monastic Prussia () or Teutonic Prussia () and existed until 1525 as a part and fiefdom of the Kingdom of Poland. The Livonian branch joined the Livonian Confederation and continued to exist as part of it until 1561.
Overview
Established in Prussia and the Polish Masovian Chełmno Land in the 13th century, the state expanded mostly as a result of the 13th-century Prussian Crusade against the pagan Baltic Prussians and the 14th-century invasions of neighboring Christian countries of Poland and Lithuania. The conquests were followed by German and Polish colonization. In addition, the Livonian Brothers of the Sword controlling Terra Mariana were incorporated into the Teutonic Order as its autonomous branch, the Livonian Order in 1237. In 1346, the Duchy of Estonia was sold by the King of Denmark for 19,000 Cologne marks to the Teutonic Order. The shift of sovereignty from Denmark to the Teutonic Order took place on 1 November 1346. At the turn of the 14th and 15th centuries, the Teutonic Order temporarily acquired the territories of Gotland and Neumark, which, however, it sold in the following decades.
Throughout its history, the Teutonic state waged numerous wars with Poland and Lithuania, encouraging the two countries to form a close alliance and personal union, which eventually led to the creation of the Polish–Lithuanian Commonwealth in the 16th century. Following its defeat in the Battle of Grunwald in 1410 the Teutonic Order fell into decline, the region of Samogitia was restored to Lithuania.
The Prussian branch of the Teutonic Order returned Pomerelia (the previously Polish regions of Chełmno Land and Gdańsk Pomerania) and ceded the western part of Prussia (Warmia, as well as parts of Pomesania and Pogesania) to Poland after the Peace of Thorn in 1466. The territories ceded to the Kingdom of Poland formed the Polish province of Royal Prussia, while the eastern part remained under Teutonic Order rule, known thereafter as the Monastic Prussia () or Teutonic Prussia (), as a feudal fief and integral part of the Kingdom of Poland. The monastic state of the Order's main (Prussian) branch was secularized in 1525 during the Protestant Reformation to become the Duchy of Prussia ruled by the House of Hohenzollern, remaining a fiefdom of the Polish Crown and later the Polish–Lithuanian Commonwealth.
The Livonian branch continued as part of the Livonian Confederation established in 1422–1435, which became a protectorate of the Grand Duchy of Lithuania in 1559, and was finally secularised and split into the Duchy of Courland and Semigalia, as well as the Duchy of Livonia in 1561, both duchies being fiefs of the Grand Duchy of Lithuania.
Background
Poles in Old Prussia
The Old Prussians withstood many attempts at conquest preceding that of the Teutonic Knights. Bolesław I of Poland began the series of unsuccessful conquests when he sent Adalbert of Prague in 997. In 1147, Bolesław IV of Poland attacked Prussia with the aid of Kievan Rus', but was unable to conquer it. Numerous other attempts followed, and, under Duke Konrad I of Masovia, were intensified, with large battles and crusades in 1209, 1219, 1220 and 1222.
The West-Baltic Prussians successfully repelled most of the campaigns and managed to strike Konrad in retaliation. However, the Prussians and Yotvingians in the south had their territory conquered. The land of the Yotvingians was situated in the area of what is today the Podlaskie Voivodeship of Poland. The Prussians attempted to oust Polish or Masovian forces from Yotvingia, which by now was partially conquered, devastated and almost totally depopulated.