The Kaufmannskirche St. Gregor (Merchant's Church St Gregory) is a 14th-century Gothic parish church at Anger Square. It is one of the largest and most important original parish churches in Erfurt. The parents of Johann Sebastian Bach, Johann Ambrosius Bach and Maria Elisabeth Lämmerhirt married here in 1668.
The former Romanesque building (11th century) on the site was burnt down in 1291. The consecration of the Gothic basilica with twin choir towers took place in 1368. The altar (1625), pulpit (1598), baptismal font (1608), epitaphs (1584/85/90) are works of the Thuringian Late Renaissance and forms of Luther iconography of Erfurt sculptors and stone masons Hans Friedemann, the Elder and Younger. Martin Luther preached here on 22th October 1522.
References:Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.