غي دي لوزينيان
Baldwin IV, who suffered from lepromatous leprosy, had made his nephew (the only son of his sister, Sybilla by her first husband), Baldwin V, his heir and co-ruler, to prevent Sybilla's second husband, Guy of Lusignan, from mounting the throne. The High Court of Jerusalem stipulated that a committee of Western European rulers was entitled to choose between Sybilla and Isabella to succeed Baldwin V if he died before reaching the age of majority, but Sybilla and Guy of Lusignan were crowned soon after Baldwin V died in 1185. Guy's opponents tried to play Isabella and her husband off against him, but Humphrey did homage to the royal couple.