Northern Crusade

The Northern Crusades or Baltic Crusades were religious wars primarily undertaken by the Christian military orders and kingdoms against the pagan Baltic, Finnic and Slavic peoples around the southern and eastern shores of the Baltic Sea. The crusades took place mostly in the 12th and 13th centuries and resulted in the conversion and baptism of indigenous peoples.

Most notable campaigns were Livonian and Prussian crusades. Some of these wars were called crusades during the Middle Ages, but others, including most of the Swedish ones, were first dubbed crusades by 19th-century romantic nationalist historians.

The official starting point for the Northern Crusades was Pope Celestine III's call in 1195; but the Christian kingdoms of Scandinavia, Poland and the Holy Roman Empire had begun moving to subjugate their pagan neighbors even earlier. The non-Christian people who were objects of the campaigns at various dates included:

Armed conflict between the Baltic Finns, Balts and Slavs who dwelt by the Baltic shores and their Saxon and Danish neighbors to the north and south had been common for several centuries before the crusade. The previous battles had largely been caused by attempts to destroy castles and sea trade routes and gain economic advantage in the region, and the crusade basically continued this pattern of conflict, albeit now inspired and prescribed by the Pope and undertaken by Papal knights and armed monks.

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