early medieval times. Two massacres of Jews occurred during the First Crusade, on (1 and 27 June 1096). On the latter occasion some Jews committed suicide in order to escape the fury of the Crusaders. In 1263 the foundation stone for the Gothic St. Victor cathedral was laid. After 281 years of construction it was finally completed in 1544. By the end of the 14th century, Xanten was surrounded by a town wall. In 1392 the northern part of the town came into the possession of the Dukes of Cleves, while the southern part remained with the Archbishopric of Cologne. The division of Xanten was a cause of a conflict between Cleves and Cologne, which ended when the whole of Xanten was awarded to the Duchy of Cleves in 1444. Early Modern period After being taken by the Dukes of Cleves, in the wake of war and crop failure, the number of inhabitants slumped from 5,000 at the beginning of the 16th century to approximately 2,500 by the end of the 18th century. The Rhine had been a basis of Xanten's status as a trading town until the river bed shifted away from the town, causing its economic situation to deteriorate. The river even flooded and destroyed the locality of Birten several times. The borough Marienbaum, however, became the main place of pilgrimage on the Lower Rhine between 1430 and 1441. In 1460 a monastery of the Bridgettines was established, with an abbey church called St. Mariä Himmelfahrt (Assumption of Mary) which nowadays serves as a parish church. In the 17th century Xanten was (along with Cleves) inherited by the Margraviate of Brandenburg. Protestantism was placed on an equal footing with the Roman Catholic Church, as confirmed by the Treaty of Xanten on 12 November 1614. Thereupon a church was built at the Großer Markt (Great Marketplace), which was expanded with a spire in 1622. Nevertheless, at the beginning of the 20th century only 5% of the population were of Protestant denomination. By the beginning of the 21st century, the Protestant share of the population had increased to some 20%. 19th and early 20th century In 1802, the Viktor-convent was secularized by Napoléon Bonaparte, and the libraries of closed monasteries and the convent library were merged. After that, the economic situation deteriorated more rapidly. A town gate called the Marstor was torn down in 1821, and the Scharntor and parts