The burning of Jan Hus at Konstanz increased religious and national agitation in Bohemia, which was tolerated by king Wenceslaus. After his death in 1419 the Czechs refused to accept Sigismund as their new king as they held him responsible for Hus's death. Sigismund in return called a Reichstag in Wrocław, the first one to the east of the Elbe, to determine actions against the revolting Czechs. Eighteen Silesian rulers rendered homage to the king and promised help. In 1421 a Silesian army repeatedly invaded northeastern Bohemia, but was defeated by the Hussites. Moravia joined the Hussite movement, isolating Silesia and Lusatia in the Bohemian lands and becoming the foremost object of hate for the radical Taborites. In January 1425 the Hussites established permanent pressure on Silesian lands, via raids labeled "beautiful rides". After 1427 the Hussites—supported by some Polish lords (Dobiesław Puchała, Sigismund Korybut) and Silesian dukes (Bolko V the Hussite)—invaded Silesia many times, destroyed more than 30 towns and ravaged the country. On the other hand, united armies of local dukes and wealthy towns (Breslau etc.) plundered Bohemian-Silesian borderland and eastern Bohemia (area around Náchod and Trutnov). Some Silesian towns, like Gliwice, Kluczbork, Niemcza or Otmuchów, became Hussite bases for several years and were a constant threat to nearby regions. The Hussite menace lasted until 1434, when they were defeated by the more moderate Ultraquists at Lipany in Bohemia. Sigismund became king of Bohemia and united Silesia (except lands of Bolko V) by a public peace and the appointment of bishop Konrad, duke of Oels, as senior governor ( ).