From the time of the young king's assumption of personal control of the government until the outbreak of the conflict with the papacy in 1076, Henry IV's main concern was with eastern Saxony. In the later 1060s and early 1070s the king stayed with unprecedented frequency in his palace of Goslar and the royal presence involved an intensification of governmental activity in the region. Grievances against the royal government provoked rebellions by individual princes in 1069 and 1070 and a much more formidable rebellion of the east Saxon and Thuringian nobility in 1073–5. There is evidence of Saxon dissatisfaction with the Salian regime, however, even before Henry IV's accession, although not on the scale of the rebellion of 1073. Henry III had aroused the suspicions of the princes by his frequent visits to Goslar and by his generosity to Saxon bishops. The fear that the emperor intended to undermine the standing of the princes provoked the unsuccessful assassination attempt by Count Thietmar Billung, brother of Duke Bernard II of Saxony, in 1047. On 10 September 1056, a month before the emperor's death, the regime suffered a serious defeat, threatening the security of eastern Saxony. Margrave William of the Saxon Nordmark was killed ‘together with an infinite multitude of the Saxon army’ in an encounter with the Slav confederation of the Liutizi. This setback, with its resultant loss of prestige and credibility, may have inspired the conspiracy of 1057 reported by the chronicler Lampert of Hersfeld.