St. Michael am Weidenbach

In 1402 Abbot Hermann of St. Pantaleon transferred the Weidenbach courtyard to six priests, whose circle gave rise to various Devotio moderna institutions in Cologne. The Brothers of the Common Life moved in in 1416, and the following year Archbishop Dietrich II of Moers approved the takeover after a university review. Heinrich von Ahaus served as the first rector.

Producing, selling, and repairing books shaped the brothers' way of life and sustained them financially into the 1580s. They also engaged in viticulture, the wine trade, and beer sales, supplementing their income with annuities and leased houses. This commercial activity repeatedly brought them into competition with Cologne's citizens and craftsmen.

Pope Eugene IV granted permission for a house chapel in 1432, and in 1434 Goswin Arnheim, Bishop of Lydda, consecrated the chapel and prayer hall—with three altars—to St. Alexius. In 1490 the building was expanded into a single-nave church on a square plan with a steep gabled roof and ridge turret, consecrated in 1491 to the Trinity, the Mother of God, and St. Michael. The convent buildings adjoined it directly to the east and west.

Returning from the Siege of Neuss in 1475, Emperor Frederick III stopped at the convent, received an ornately decorated book from the brothers, and placed the community under his protection. Around 1500 the community grew further, reflected in rising membership and book output. After 1793 the French occupation used the buildings as a house of correction and prison, and from 1802 as barracks; their expansion destroyed the church in 1827.