River Brethren, name used to designate certain Christian bodies originating in 1770, during a revival movement among German settlers in E Pennsylvania. In the 1750s, Mennonite refugees from Switzerland had established their homes near the Susquehanna River. Their religious leaders, Jacob and John Engle, became associated with the revival, and their followers came to be known as the River Brethren, possibly because they were baptized in the Susquehanna upon joining the brotherhood. Several factions of the River Brethren withdrew in the mid-19th cent., including the Yorker Brethren and the United Zion Church, while the main body took the name Brethren in Christ, by which a group of Mennonites is also known. The Brethren practice trine (triple, in allusion to the Trinity) immersion and foot washing, adhere to plain dress, and oppose war, alcohol, tobacco, and worldly pleasures. There were about 11,000 members in the United States and Canada in 1992. They carry out missionary work in Asia and Africa.