the Sachenkirch and Sachwitz families. Post the Mongol invasion After the Mongol invasion the town was partly populated by German settlers who, in the ensuing centuries, gradually became its dominant population. The city, however, retained its multi-ethnic character, a reflection of its importance as a trading post on the junction of the Via Regia and the Amber Road. With the influx of settlers, the town expanded and in 1242 came under German town law. The city council used both Latin and German, and the early forms of the name Breslau, the German name of the city, appeared for the first time in its written records. Polish gradually ceased to be used in the town books, while it survived in the courts until 1337, when it was banned by the new rulers, the german speaking House of Luxembourgs. The enlarged town covered around , and the new main market square, surrounded by timber-frame houses, became the trade centre of the town. The original foundation, Ostrów Tumski, became its religious centre. The city gained Magdeburg rights in 1261. While the Polish Piast dynasty remained in control of the region, the ability of the city council to govern itself independently increased. In 1274 prince Henryk IV Probus gave the city its staple right. In the 13th century, two Polish monarchs were buried in Wrocław churches founded by them, Henry II the Pious in the St. Vincent church and Henryk IV Probus in the Holy Cross church. Wrocław, which for 350 years had been mostly under Polish hegemony, fell in 1335, after the death of Henry VI the Good, to John of Luxembourg. His son Emperor Charles IV in 1348 formally incorporated the city into the Holy Roman Empire. Between 1342 and 1344, two fires destroyed large parts of the city. In 1387 the city joined the Hanseatic League. On 5 June 1443, the city was rocked by an earthquake, estimated at ca. 6 on the Richter scale, which destroyed or seriously damaged many of its buildings. Between 1469 and 1490, Wrocław was part of the Kingdom of Hungary, and king Matthias Corvinus was said to have had a Vratislavian mistress who bore him a son. In 1474, after almost a century, the city left the Hanseatic League. Also in 1474, the city was besieged by combined Polish-Czech forces. However, in November 1474, Kings Casimir IV of Poland, his son Vladislaus II of Bohemia,