Raymond of Poitiers (1099-June 27 1149) was prince of Antioch between 1136 to 1149. He was the youngest son of William IX, duke of Aquitaine and his wife Philippa, countess of Toulouse.

Following the regencies of Baldwin II of Jerusalem (1130-1131) and Fulk of Jerusalem (1131-1136), Raymond assumed the control of the principality of Antioch by his marriage in 1136 with the heiress of Bohemund II of Antioch, Constance, a child of ten years of age. The marriage had the blessing of the Patriarch of Antioch, but not of Alice of Antioch, the mother of the bride, who believed that Raymond was intended to be her husband.

The first years of Raymond and Constance's joint rule were spent with conflicts with the Byzantine Emperor John II Comnenus, who had come south partly to recover Cilicia from Leo of Armenia, and to reassert his rights over Antioch. Raymond was forced to do homage, and even to promise to cede his principality as soon as he was recompensed by a new fief, which John promised to carve for him in the Muslim territory to the east of Antioch. The expedition of 1138, in which Raymond joined with John, and which was to conquer this territory, naturally proved a failure: Raymond was not anxious to help the emperor to acquire new territories, when their acquisition only meant for him the loss of Antioch. John Comnenus returned unsuccessful to Constantinople, after demanding from Raymond, without response, the surrender of the citadel of Antioch.

There followed a struggle between Raymond and the patriarch. Raymund was annoyed by the homage which he had been forced to pay to the patriarch in 1135 and the dubious validity of the patriarch's election offered a handle for opposition. Eventually Raymond triumphed, and the patriarch was deposed (1139). In 1142 John Comnenus returned to the attack, but Raymond refused to recognize or renew his previous submission; and John, though he ravaged the neighborhood of Antioch, was unable to effect anything against him. When, however Raymond demanded from Manuel, who had succeeded John in 1143, the cession of some of the Cilician towns, he found that he had met his match. Manuel forced him to a humiliating visit to Constantinople, during which he renewed his oath of homage and promised to acknowledge a Greek patriarch.

In the last year of Raymond's life Louis VII and his wife Eleanor of Aquitaine (Raymond's niece) visited Antioch. Raymond sought to prevent Louis from going south to Jerusalem, and to induce him to stay in Antioch and help in the conquest of Aleppo and Caesarea. At any rate Louis hastily left Antioch, and Raymond was balked in his plans. In 1149 he was killed in the battle of Inab during an expedition against Nur ad-Din.

Raymond is described by William of Tyre (the main authority for his career) as "a lord of noble descent, of tall and elegant figure, the handsomest of the princes of the earth, a man of charming affability and conversation, open-handed and magnificent beyond measure"; pre-eminent in the use of arms and military experience; litteratorum, licet ipse illiteratus esset, cultor ("although he was himself illiterate, he was a cultivator of literature" - he caused the Chanson des chétifs to be composed); a regular churchman and faithful husband; but headstrong, irascible and unreasonable, with too great a passion for gambling (bk. xiv. c. xxi.). For his career see Rey, in the Revue de l'orient latin, vol. iv.