The Church of the Brethren, also known as the St. Vrain Church of the Brethren and the Old Dunkard Church, is an historic Church of the Brethren meeting house located on Hygiene Road in Hygiene in the St. Vrain Valley of Boulder County, Colorado. In 1874, formal organization of the Church of the Brethren was held at the ranch home of Mr. and Mrs. J. R. Ullery led by the itinerant preacher, James R. Gish.