Reginald of Châtillon (born, Châtillon-sur-Loing, France—died July 4, 1187, Galilee, Palestine [now in Israel]) was a prince of Antioch (1153–60), one of the leading military figures of the Crusades between 1147 and 1187, whose reckless policy in raiding Muslim caravans during periods of truce led to the virtual destruction of the Latin kingdom of Jerusalem and the loss of most of its territory.
Reginald left for the Holy Land in 1147 and put himself at the service first of King Baldwin III of Jerusalem and then of Constance of Antioch. Constance, whose first husband had died in 1149, fell in love with Reginald and married him in 1153.
As prince of Antioch, Reginald was cruel and violent. He treated the patriarch Aimery with outrageous cruelty to extort money from him. At the instigation of the Byzantine emperor Manuel I Comnenus, he attacked Armenian Cilicia (southeastern Anatolia), but subsequently he made peace with Thoros II of Cilicia and joined him in an invasion of Byzantine Cyprus. Manuel had his revenge in 1159 when Reginald was obliged to acknowledge himself as his vassal. The following year Reginald was taken prisoner by the Muslims and held captive until 1176.
Meanwhile, Constance had died (1163), leaving Antioch to Bohemond III, her son by her first husband. Reginald therefore returned to Jerusalem and in 1177 married Stephanie, widow of the seigneur d’Outre-Jourdain (east and south of the Dead Sea), thus becoming prince of Krak du Désert (Kerak) and of Montréal. Reginald’s new strongholds controlled Muslim trade routes, and in the summer of 1181 he plundered a Muslim caravan, thus violating the truce of 1180. When Saladin asked the king of Jerusalem to make Reginald restore the plunder, Reginald refused and war broke out. Reginald launched five galleys on the Red Sea: they not only blockaded the Muslim port of Eilat (Elath) but also harassed shipping, raided other ports, and even threatened Mecca until an Egyptian fleet destroyed them. On land, King Baldwin IV’s army relieved Krak from two sieges by Saladin (1183 and 1184).
In 1186 Reginald was instrumental in upsetting arrangements for the succession to Baldwin V and in securing the coronation of Sibyl (sister of Baldwin IV) and her husband, Guy of Lusignan, as sovereigns of Jerusalem. At the end of 1186 Reginald again broke a truce with Saladin by plundering a caravan in which a sister of Saladin was traveling. When King Guy asked Reginald to return the stolen property, he refused, and war broke out again. Reginald was taken prisoner in the Battle of the Horns of Ḥaṭṭin (July 4, 1187) and conducted to Saladin’s tent. Saladin upbraided him for his truce breaking in violation of his oath, and he was beheaded on the spot, by Saladin himself.