 Congressman Thaddeus Stevens, who had practiced law in Lancaster County since at least 1838.The oldest surviving dwelling of European settlers in the county is that of Mennonite Bishop Hans Herr, built in 1719.In 1989, Donald Kraybill counted 37 distinct religious bodies/organizations, with 289 congregations and 41,600 baptized members, among the plain sects who are descendants of the Anabaptist Mennonite immigrants to Lancaster County.