Raynald of Châtillon, also known as Reynald or Reginald of Châtillon (French: Renaud de Châtillon; c. 1125 – 4 July 1187), was Prince of Antioch from 1153 to 1160 or 1161, and Lord of Oultrejordain from 1175 until his death. He was born as his father's second son into a French noble family. After losing a part of his patrimony, he joined the Second Crusade in 1147.
Raynald led the crusader army that defeated Saladin at the Battle of Montgisard. He was the only Christian leader to pursue an offensive policy against Saladin, making plundering raids against the caravans travelling near his domains. He built a fleet of five ships which plundered the coast of the Red Sea, threatening the route of the Muslim pilgrims towards Mecca in early 1183. He swore to defile the sacred cities, to drag the body of the Prophet Muhammad from his tomb, and to destroy the Kaaba, Islam's most sacred place. Saladin pledged that he would never forgive Raynald.
Raynald was a firm supporter of Baldwin IV's sister, Sybilla, and her husband, Guy of Lusignan, during conflicts regarding the succession of the king. Sibylla and Guy were able to seize the throne in 1186 due to Raynald's co-operation with her uncle, Joscelin III of Courtenay. Raynald attacked a caravan travelling from Egypt to Syria in late 1186 or early 1187, claiming that the truce between Saladin and the Kingdom of Jerusalem did not bind him. After Raynald refused to pay a compensation, Saladin invaded the kingdom and annihilated the crusader army in the Battle of Hattin. Raynald was captured in the battlefield. Saladin personally beheaded him after he refused to convert to Islam. Most historians have regarded Raynald as an irresponsible adventurer whose lust for booty caused the fall of the Kingdom of Jerusalem.