In the Middle Ages, conversion to Christianity was often a political matter, and there was much influence to be gained by bringing conversion to another kingdom. Lithuania, the last pagan kingdom in East Central Europe in the early 1300s, faced a losing battle with the crusading Teutonic Knights, who had gained influence and control over several of Lithuania's neighbors through conversion. Lithuania's choice to convert to Christianity through a union with Poland instead was intended to remove the legitimacy of the Teutonic Knights' crusade without putting Lithuania under the control of a much stronger power. Though the conversion had more to do with political survival than religious feeling, the Polish-Lithuanian Union that followed became a new power in the region and helped shape the history of East Central Europe for the next 300 years.