The first large groups of Swiss, Low German, and Hutterian Brethren immigrated from Russia to Dakota Territory, with the first group of fifteen families arriving in Yankton on October 17, 1873. A mass movement of several hundred families followed in 1876, and smaller groups arrived throughout the 1870s. The Mennonites settled mainly in Hutchinson, Turner, and Bon Homme counties. The Mennonites and Hutterian Brethren originated in the Anabaptist wing of the Reformation that began in central Europe. Their belief in the separation of church and state and in nonresistance led to severe persecution for about three centuries, and after being driven from country to country in Europe, they finally came to America for asylum. Their first years in Dakota Territory were threatened by severe winters, grasshoppers, prairie fires, and drought, but hard work, unwavering faith in God, and financial aid from Mennonite organizations helped them survive those critical years.