Baldwin IV (1161–1185), known as the Leper King, was the king of Jerusalem from 1174 until his death in 1185. Baldwin ascended to the throne when he was thirteen despite having leprosy. He launched several attempts to curb the increasing power of the Muslim ruler Saladin, though much of his life was marked by infighting amongst the kingdom's nobles. Throughout his reign, and especially at the end of his life, he was troubled by his succession, working to select a suitable heir and prevent a succession crisis. Choosing competent advisers, Baldwin ruled a thriving crusader state, protecting it from Saladin.
Baldwin's parents, King Amalric and Agnes of Courtenay, separated when Baldwin was two. At nine years old, he was sent to be educated by Archbishop William of Tyre.