what is unionskirche, idstein?
It is the active Protestant parish church of Idstein.
Unionskirche, Idstein
The Unionskirche (Union Church) is the active Protestant parish church of Idstein, a town in the Rheingau-Taunus district in the German state of Hesse. 
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Unionskirche, Idstein [SEP] Introduction
The Unionskirche (Union Church) is the active Protestant parish church of Idstein, a town in the Rheingau-Taunus district in the German state of Hesse. Idstein was a residence of the counts of Nassau. The church building in the center of the historic "Altstadt" (old town) dates back to the 14th century when it was built as a collegiate church. It became Lutheran during the Reformation. Its interior was adapted in the 17th century to become a Lutheran "Predigt- und Hofkirche" (sermon and court church). The most prominent decoration in the church is the series of 38 paintings by the Flemish painter Michael Angelo Immenraedt, an exponent of Flemish Baroque painting, and others.