Baldwin IV (1161 – 1185), the son of Amalric I of Jerusalem and his first wife Agnes of Edessa, was king of Jerusalem from 1174 to 1185.

Political manoeuvering

Baldwin spent his youth in his father's court in Jerusalem, having little contact with his mother, the countess Agnes of Courtenay. Baldwin IV was educated by the historian William of Tyre, and came to the throne at the age of thirteen. In his minority the kingdom was ruled by two susccessive regents, first Miles of Plancy, though unofficially, and then Raymond III of Tripoli. As Baldwin suffered from leprosy, he was not expected to reign long or even produce an heir, and courtiers and lords positioned themselves for influence over Baldwin's heirs, his sisters the princesses Sibylla and Isabella. Sibylla was being raised by her great-aunt, Ioveta (Queen Melisende's sister), in the convent of Bethany, and Isabella was in the court of her mother, the dowager-queen Maria Comnena, in Nablus.

In his capacity as regent, Raymond of Tripoli had the princess Sibylla married to William of Montferrat in autumn 1176. William was also created Count of Jaffa and Ascalon. However, William died the following June, leaving the widowed Sibylla pregnant with the future Baldwin V.

It was in this year that the king's distant cousin, Philip of Flanders, came to Jerusalem on Crusade. Phillip demanded to wed Baldwin's sisters to his vassels. Phillip, as Baldwin's next male kin on his paternal site, claimed authority superceding Raymond's regency. The Haute Cour refused to agree to this, with Baldwin of Ibelin publically insulting Philip. Offended, Philip left the kingdom, campaigning instead for Antioch. The Ibelin family were patrons of the dowager-queen Maria, and historian Bernard Hamilton suggests that Baldwin of Ibelin acted this way in hopes of marrying one of Baldwin's sisters himself.

Baldwin's rule

Baldwin reached majority later that same year, and Raymond of Tripoli stepped down. Disadvantaged, young Baldwin had few male relatives to whom royal power could be delegated. The king turned to his mother and her brother, Joscelin III, the titular count of Edessa. Agnes, growing in influence both at court and over her son and her daughter, Sibylla, had Baldwin appoint Joscelin as seneschal.

In 1177 Baldwin IV allowed his step-mother the dowager-queen to marry Balian of Ibelin. This was a dangerous allience, allowing Maria to marry into the Ibelin family, as they had become very ambitious. With Maria's patronage, the Iblin's plotted to have the princesses Sibylla and Isabella married into their family.

Later in 1177, Baldwin and Raynald of Chatillon (the former prince of Antioch through marriage to Constance) defeated Saladin at the Battle of Montgisard. In 1176 Raynald had been released from captivity in Aleppo, and later Baldwin created him lord of Kerak, a fortress to the east of the Dead Sea.

In the summer of 1183, Agnes had Baldwin IV marry Sibylla to Guy of Lusignan, the constable Amalric of Lusignan's brother. Baldwin also appointed Guy regent and to rule during his illnesses with lepersy.

By this arrangement Agnes' influence in the kingdom was at its height. She held direct influence over her son the king, over her son's heir Sibylla, and Guy of Lusignan owed his advancment directly to her. Additionally, Agnes also had Baldwin marry the eight-year-old princess Isabella to Humphrey IV of Toron, an ally to Agnes, thus neutralizing the Ibelin-Maria faction.

Later in 1183, Baldwin had become offended by Guy's actions as regent. Guy was at the wedding festivities for Isabella and Humphrey, held in Kerek. However, the festivites were interrupted by Saladin, now beseiging the fortress with the wedding guests inside. Baldwin marshalled what strength he had and lifted the seige. Guy had previously allied himself with Raynald, who was by now taking advantage of his position at Kerak to harass the trading caravans travelling between Egypt and Damascus. After Saladin retaliated for these attacks in 1182, Baldwin was forced to name Guy regent, but Guy refused to fight Saladin and Saladin's troops simply went home. Baldwin could not tolerate this and deposed Guy as regent. In disgrace, Guy retired to Ascalon, taking his wife the princess Sibylla with him.

Failing health and death

According to Hamilton, there was no evidence to suggest princess Sibylla was herself disgraced by her second husband's actions, or even held in disfavour by the king, but in the early months of 1184 Baldwin attempted to have the marriage between Sibylla and Guy annulled. The couple had foiled this attempt by holding fast in Ascalon, not attending the annullment proceedings. Failing to pry his sister away from Guy, Baldwin appointed his nephew as heir and successor, with the support of Agnes, Raymond, and many of the other barons, excluding Sibylla from the succession. Raymond was to act as guardian of the infant heir, and later as regent if Baldwin IV was to expire, but Baldwin IV himself would continue to rule with Agnes herself as his advisor.

The military expedition to relieve Kerak and the dynastic struggle had weakened Baldwin considerably. Agnes retired to Acre in the early months of 1184, and may have died before Baldwin's own death in 1185. Though often suffering from the effects of leprosy and ruling with regency governments, he was able to maintain himself as king for much longer than otherwise might have been expected.

Sources

• Medieval Women, edited by Derek Baker. The Ecclesiastical History Society, 1978
• The Leper King and his Heirs, by Bernard Hamilton.