The Reformed tradition centered in the state of Pennsylvania, particularly the eastern and central counties of that state, and extended westward toward Ohio and Indiana and southward toward Maryland, Virginia, and North Carolina in the first generation of immigration. Early Reformed adherents settled alongside Lutheran, Schwarzenau Brethren/German Baptists, and sometimes Anabaptist/Mennonite neighbors. Some Reformed congregations in Pennsylvania and North Carolina formed union churches with Lutherans, sharing the same building but operating as separate entities, although they frequently shared Sunday Schools and occasionally ministers.