Protestantism, movement that began in northern Europe in the early 16th century as a reaction to medieval Roman Catholic doctrines and practices. Along with Roman Catholicism and Eastern Orthodoxy, Protestantism became one of three major forces in Christianity. After a series of European religious wars in the 16th and 17th centuries, and especially in the 19th century, it spread throughout the world. Wherever Protestantism gained a foothold, it influenced the social, economic, political, and cultural life of the area.