St. Martin's Church

St. Martin's Church, Biberach is a church in Biberach an der Riß, in the Upper Swabia region of the German state of Baden-Württemberg. It is the oldest still active Simultaneum or shared church in Germany. Its two congregations form part of the Roman Catholic Diocese of Rottenburg-Stuttgart and the Lutheran Evangelical Regional Church in Württemberg, respectively.
St. Martin's was built in 1337-1366 and served as the parish church of Biberach before the Reformation. With the conversion of almost the entire population of the town to Lutheranism, the church was used for Lutheran services. Then, in 1548 the Holy Roman Emperor Charles V ordered that Catholic services be resumed. The solution was to divide the church, with Catholic services held in the former choir and Lutheran services in the larger nave. The arrangement was made permanent by the Peace of Augsburg.

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