Simultaneum

[1] Simultaneum as a policy was particularly attractive to rulers who ruled over populations which contained considerable numbers of both Catholics and Protestants.

[1] During the Nine Years' War (1688–1697), Louis XIV of France occupied the Electorate of the Palatinate, a Protestant region situated mainly in the western part of what is today Germany, where he introduced the simultaneum.

At the end of the war the region returned to Protestant control, but a last-minute addition to the Treaty of Ryswick provided for a continuation of the simultaneum.

The main traditional pilgrim churches of Jerusalem and Bethlehem are shared between several denominations.

The regulatory work is known as the "Status quo", a type of church-sharing which is in no way related to the West European Protestant-Catholic sharing system described here (the "simultaneum").

Following the compromise between the Reformed Aniconism and Lutheran Adiaphora in Ringstedt's Reformed-Lutheran simultaneum of St. Fabian there is a Lutheran altar, but it shows no crucifix, but only candles.
Map of all simultaneum churches in Germany
Lutheran and Catholic altars in St. M. Kozal church in Gniezno , Poland
Triple in New York. A United Methodist church, now shared by Jewish , and Presbyterian congregations.