He played a great part in the politics of the Great Interregnum in Germany. He left the Hohenstaufen fold and supported William II of Holland as king. He was sent in an embassy to Henry III of England and after William's death, supported Henry's brother Richard, earl of Cornwall, as king. In 1272, he was party to the nobles who offered the crown to Ottokar II of Bohemia and then Rudolph of Habsburg.
In 1252, he intervened in the War of the Succession of Flanders and Hainault, at the side of Jean d'Avesnes. After 1258, he fell out with John I of Brabant, putting an end to sixty years of good relations with the dukes of Brabant.