The parish church of St Mary's was first mentioned in 1283. Stendal quickly prospered as a centre of commerce and trade; it received city walls about 1300, the citizens joined the Hanseatic League in 1358 and purchased the privilege of minting from the Brandenburg margraves in 1369. A Latin school is documented from 1338. In 1456 the Hohenzollern elector Frederick II Irontooth founded a convent of Augustinian nuns, which today is the site of a museum. In 1502 his descendant Elector Joachim I Nestor married Princess Elizabeth of Denmark at Stendal. Magnificent churches, the town hall and the two remaining city gates are still proof of Stendal's former wealth.