Baldwin IV of Jerusalem: The Leper King Who Fought Saladin

Baldwin IV (1161–1185) was king of the crusader Kingdom of Jerusalem from 1174 until his death, ruling for eleven years while suffering from leprosy. Known as the Leper King, he won a famous victory over Saladin at Montgisard in 1177 and kept the kingdom intact against a rising Muslim power. His illness, however, left the succession uncertain and fed the factional quarrels that weakened the kingdom just before its collapse in 1187.

Background: a kingdom under pressure

The Kingdom of Jerusalem had been founded after the First Crusade captured the city in 1099. By the 1170s it was a small feudal state stretching along the coast of the Levant and inland to the Jordan valley, with a ruling class of Frankish (western European) nobles, powerful military orders and a largely local Christian and Muslim population.

Its strategic position was worsening. Under Nur ad-Din, Muslim Syria had been united around Damascus and Aleppo, and in 1169 his officer Saladin became master of Egypt. When Nur ad-Din died in May 1174, Saladin began to absorb his Syrian lands as well. For the first time the crusader states faced a single ruler controlling both Egypt and much of Syria.

Baldwin was born in 1161, the son of the future King Amalric and his first wife, Agnes of Courtenay. When Amalric became king in 1163, the church required him to annul his marriage to Agnes, but Baldwin and his sister Sibylla were recognised as legitimate heirs.

A diagnosis in childhood

The chronicler William of Tyre, who was Baldwin’s tutor, records how the disease was discovered. When the prince was about nine, he played a rough game with other boys who scratched one another’s arms, and Baldwin felt no pain. William saw this as a sign of patience at first, then realised something was wrong. Physicians treated the boy without success.

Historians generally agree that Baldwin had lepromatous leprosy, the most severe form of the disease. The illness became more obvious after puberty. By his early twenties he had lost the use of his hands and feet and much of his sight. Medieval society often isolated lepers, but Baldwin was accepted as king because he was the only son of Amalric and because the nobility preferred a legitimate ruler to a disputed succession.

Accession and regency

Amalric died on 11 July 1174 and Baldwin, aged 13, was crowned on 15 July 1174. The seneschal Miles of Plancy governed at first, but he was murdered in Acre in the autumn of 1174. Count Raymond III of Tripoli, the king’s closest adult male relative, then became regent and held the post until Baldwin came of age at 15 in 1176.

Because everyone knew that Baldwin was unlikely to father children or live long, the marriage of his sister Sibylla became a central political question. In 1176 she married William Longsword of Montferrat, a well-connected Italian noble, but he died in 1177 leaving her pregnant with the future Baldwin V.

Montgisard and the war with Saladin

In the autumn of 1177 Saladin invaded the kingdom from Egypt while a large part of the Frankish army was campaigning in northern Syria with Count Philip of Flanders. Baldwin gathered what troops he could and, together with the Templars and Raynald of Châtillon, surprised Saladin’s scattered forces near Ramla on 25 November 1177. The Battle of Montgisard ended in a rout, and Saladin escaped to Egypt with heavy losses.

The victory did not end the threat. In 1178–1179 Baldwin built a castle at Jacob’s Ford on the upper Jordan to watch the road to Damascus. Saladin defeated the Franks at Marj Ayyun in June 1179 and then captured and destroyed the unfinished castle in August 1179. A two-year truce followed in 1180.

When fighting resumed, Baldwin led his army in person despite his illness. In 1182 he faced Saladin near Belvoir Castle in an indecisive battle, and in 1183 and 1184 he relieved Raynald of Châtillon’s fortress of Kerak, east of the Dead Sea, when Saladin besieged it. By then the king had to be carried in a litter.

Key people at court

Baldwin’s reign was shaped by rivalries among the people around him:

• Agnes of Courtenay, the king’s mother, who returned to court and gained great influence over appointments.
• Raymond III of Tripoli, an experienced lord with strong local ties, twice regent of the kingdom.
• Sibylla, the king’s sister and heir, and her second husband Guy of Lusignan, a newcomer from Poitou whom she married in 1180.
• Raynald of Châtillon, lord of Oultrejordain (the lands east of the Jordan), whose raids, including a Red Sea expedition in 1182–1183, provoked Saladin.
• Heraclius, appointed Patriarch of Jerusalem in 1180, and William of Tyre, chancellor of the kingdom and its leading historian.

Modern historians once described these rivalries as a simple clash between a “court party” of newcomers and a “native” baronial party. Bernard Hamilton and others have shown that alliances shifted frequently and were driven more by family ties and personal interest.

The crisis of the succession

In 1183, too ill to govern, Baldwin made Guy of Lusignan regent. Later that year Guy led the army against Saladin near the spring of Goliath in Galilee but avoided battle, which many barons saw as a failure. Baldwin removed him as regent and tried to have Sibylla’s marriage annulled, without success.

To exclude Guy from the throne, Baldwin had his nephew, aged about five, crowned co-king as Baldwin V on 20 November 1183. Shortly before his own death the king appointed Raymond III as regent for the boy. Baldwin IV died in Jerusalem in the spring of 1185, aged 23; the date is usually given as March, though some historians place it as late as May.

Consequences

Baldwin V died in 1186, still a child. Sibylla then outmanoeuvred Raymond’s supporters, was crowned queen and placed the crown on Guy’s head. Raymond refused to accept the new king and for a time made his own truce with Saladin. The divided kingdom met Saladin’s full army in July 1187 at the Battle of Hattin, where the Frankish field army was destroyed. Jerusalem surrendered in October 1187.

Historians debate how far Baldwin’s illness caused this collapse. His leprosy meant years of regencies and uncertainty, and his attempts to manage the succession deepened divisions. Yet he also held the kingdom together during a decade in which Saladin’s resources grew dramatically.

Myths and facts

• Myth: Baldwin IV wore a silver mask. No medieval source mentions a mask. The image comes from Ridley Scott’s 2005 film Kingdom of Heaven.
• Myth: he was a figurehead. Contemporary sources show him leading campaigns, appointing officials and taking major political decisions until the final months of his life.
• Fact: his leprosy was well known throughout his reign, yet the nobility accepted him as king and he remained on the throne until his death.

Timeline

• 1161: Baldwin is born, son of Amalric and Agnes of Courtenay.
• c. 1170: William of Tyre notices the first signs of the prince’s leprosy.
• 1174, 15 July: Baldwin is crowned king, four days after his father’s death.
• 1176: Baldwin comes of age and Raymond III’s regency ends.
• 1177, 25 November: Baldwin defeats Saladin at Montgisard.
• 1179, August: Saladin destroys the new castle at Jacob’s Ford.
• 1180: Sibylla marries Guy of Lusignan; a truce is agreed with Saladin.
• 1183, 20 November: Baldwin’s nephew is crowned co-king as Baldwin V.
• 1185, spring (probably March): Baldwin IV dies in Jerusalem, aged 23.

Why it matters

Baldwin IV’s reign shows how personal circumstances could shape the fate of a medieval state. A capable and determined ruler, he won the most celebrated crusader victory over Saladin, yet his incurable illness left a succession crisis that helped bring about the kingdom’s defeat two years after his death.