Baldwin IV of Jerusalem Baldwin IV of Jerusalem Baldwin IV (; ; 1161 – 16 March 1185), called "the Leper", or The Leper King, reigned as King of Jerusalem from 1174 until his death. He was the son of Amalric I of Jerusalem and his first wife, Agnes of Courtenay. Baldwin spent his childhood in his father's court in Jerusalem, having little contact with his mother, Agnes of Courtenay, Countess of Jaffa and Ascalon, and later Lady of Sidon, whom his father had been forced to divorce. Baldwin IV was educated by the historian William of Tyre (later Archbishop of Tyre and Chancellor of
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