Why did Lithuania accept Roman Catholicism in 1387?

Lithuania’s formal acceptance of Roman Catholicism in 1387 was primarily a strategic political decision made by Grand Duke Jogaila to secure an essential alliance with Poland.12

Facing mounting military pressure from the Teutonic Order in the west, Lithuania required a powerful ally. Jogaila concluded the Union of Krewo in 1385, which required him to adopt Roman Catholicism, marry the Polish queen Jadwiga, and ascend to the Polish throne. This agreement effectively integrated Lithuania into the Western Christian world, removing the religious justification for the Teutonic Knights' crusades against the region.1234

Beyond military security, the conversion facilitated the adoption of Western feudal structures. Newly baptized nobles were granted extensive privileges, and the move pushed Lithuania culturally toward the West. While the decision was driven by political necessity, it also reflected the influence of the church and the personal commitment of Queen Jadwiga to the expansion of Christianity.4513