Baldwin of Ibelin year, the king betrothed his younger half-sister Isabella of Jerusalem, Balian's stepdaughter, to Humphrey IV of Toron, to further reduce the Ibelins' influence. In 1183 he supported Raymond against Guy, who was by now regent for the ailing Baldwin IV. Lord Baldwin was among the barons who advised the king to crown Sibylla's son Baldwin V in 1183, while Baldwin IV was still alive; this was an attempt to prevent Guy from succeeding as king. Baldwin V became sole king while still a child in 1185, and when the young king died in 1186, Sibylla was crowned queen with Guy
Baldwin I, Latin Emperor of this land. After Philip II of France took Baldwin's brother, Philippe of Namur, prisoner, Baldwin was forced to agree to a truce to ensure his safety. The Treaty of Péronne was signed in January 1200 on the condition that Baldwin receive the territories he had won during the war. Baldwin was made the vassal of Philip II, and the king returned portions of Artois to Baldwin. In this fight against the French king, Baldwin allied with others who had quarrels with Philip, including kings Richard I and John of England, and the German King Otto IV. A month after