The original St. Foillan was built in 1180 as a place of worship for the hoi polloi who did not have access to the Cathedral that was constructed around the Palatine Chapel within Charlemagne's Palace of Aachen. It was first enlarged in 1414 before it was rebuilt in the Gothic style in 1482. It suffered significant damage during WWII especially in the bombing raids on the Tuesday after Easter 1944. Aachen architect and cathedral master builder Leo Hugot rebuilt it 1956-1958 by fusing surviving Gothic parts with modern construction.
The church inherited the 1910 Klais organ from St. Nikolaus in 2010, with which it shares a parish.
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