 This practice had only been introduced by emperor Henry III, yet became one of the causes for Henry IV's conflict with the Pope.In Mainz on January 7, 1106 Conrad I was invested with ring and staff as the new Archbishop of Salzburg.In 1107, the Salians occupied the bishoprics of Halberstadt, Magdeburg, Speyer and Verdun with the expressed participation of and approval by the princes.