FULK, king of Jerusalem (b. 1o92), was the son of Fulk count of Anjou, and his wife Bertracla (who ultimately deserted her husband and became the mistress of Philip I. of France). He became count of Anjou in '109, and showed himself a doughty opponent to Henry I. of England,' against whom he continually supported Louis VI. of France, until in 1127 Henry won him over by betrothing his daughter Matilda to Fulk's son Geoffrey Plan tagenet. Already in 1120 Fulk had visited the Holy Land, and become a close friend of the Templars. On his return he assigned to the order of the Templars an annual subsidy, while he also maintained two knights in the Holy Land for a year. In 1I28 he was preparing to return to the East, when he received an embassy from Baldwin II., king of Jerusalem, who had no male heir to succeed him, offering his daughter Melisinda in marriage, with the right of eventual succession to the kingdom. Fulk accepted the offer; and in 1129 he came and was married to Melisinda, receiv ing the towns of Acre and Tyre as her dower. In 1131 he became king of Jerusalem. His reign is not marked by any considerable events: the kingdom which had reached its zenith under Baldwin II., and did not begin to decline till the capture of Edessa in the reign of Baldwin III., was quietly prosperous under his rule. In the beginning of his reign he had to act as regent of Antioch, and to provide a husband, Raymund of Poitou, for the infant heiress Constance. But the great problem with which he had to deal was the progress of the atabeg Zengi of Mosul. In 1137 he was beaten near Barin, and escaping into the fort was surrounded and forced to capitulate. A little later, however, he greatly improved his position by strengthening his alliance with the vizier of Damascus, who also had to fear the progress of Zengi (114o); and in this way he was able to capture the fort of Banias, to the north of Lake Tiberias. Fulk also strengthened the kingdom on the south; while his butler, Paganus, planted the fortress of Krak to the south of the Dead Sea, and helped to give the kingdom an access towards the Red Sea, he himself constructed Blanche Garde and other forts on the S.W. to overawe the garrison of Ascalon, which was still held by the Mohammedans, and to clear the road towards Egypt. Twice in Fulk's reign the eastern emperor, John Comnenus, ap peared in northern Syria (1137 and 1142) ; but his coming did not affect the king, who was able to decline politely a visit which the emperor proposed to make to Jerusalem. In 1143 he died, leaving two sons, who both became kings, as Baldwin III. and Amalric I.
Fulk continued the tradition of good statesmanship and sound churchmanship which Baldwin I. and Baldwin II. had begun. Un fortunately he neglected to envisage the needs of the northern principalities, and to head a combined resistance to the rising power of Zengi of Mosul.