The Lithuanian Crusade was a series of economic Christian colonization campaigns by the Teutonic Order and the Livonian Order, two crusading military orders, under the religious pretext of forcibly Christianizing the “pagan” Grand Duchy of Lithuania into Roman Catholicism. The Livonian Order occupied Riga in 1202 and the Teutonic Order conquered Culmerland in 1230s. They first conquered other neighboring Baltic tribes – Curonians, Semigallians, Latgalians, Selonians, Old Prussians (see Livonian Crusade and Prussian Crusade). The first raid against the Lithuanians and Samogitians was in 1208 and the Orders played a key role in Lithuanian politics, but they were not a direct and immediate threat until 1280s. By that time the Grand Duchy of Lithuania was already a centralized state and could mount centralized defense. Thus for the next century the Order organized annual colonialist reise (raids) into the Samogitian and Lithuanian lands without great success but at immense human cost: border regions in Samogitia and Suvalkija became sparsely inhabited wilderness (de:Große Wildnis, lit. dykra) due to ethnic cleansing and genocide, although the Order gained very little territory. The war between the Teutonic Order and Lithuania was one of the longest wars in the history of Europe.
The Grand Duchy finally converted to Christianity in 1386, when Grand Duke Jogaila accepted baptism from Poland before his wedding to reigning Queen Jadwiga and coronation as King of Poland. However, the baptism did not stop the crusade as the Order publicly challenged sincerity of the conversion at the Papal court. Lithuania, together with its new ally Poland, defeated the Order in the decisive Battle of Grunwald in 1410, which is often cited as the end of the Lithuanian Crusade. The final peace was reached by the Treaty of Melno (1422).
It was the end of 225 years long warfare (1197–1422), including 86 years of the initial confrontation (1197–1283), 128 years of the regular warfare (1283–1411) and 11 years of the final fights (the period between the Peace Treaty of Thorn 1411 and the Peace Treaty of Melno 1422).