Isabella I of Jerusalem tried to play Isabella and her husband off against him, but Humphrey did homage to the royal couple. Isabella was the daughter of Amalric, King of Jerusalem, by his second wife, Maria Comnena. Maria Comnena (who was a grandniece of the Byzantine Emperor, Manuel I Komnenos) married Amalric on 29 August 1171. Isabella was born before September 1172. Amalric died unexpectedly on 11 July 1174. His son by his first marriage, Baldwin IV, was crowned king two weeks later. Before long, it became obvious that Baldwin suffered from lepromatous leprosy. To secure the succession of the ailing king, his sister,
King of Jerusalem named Guy as "bailli". Raymond contested this, but when Guy fell out of favour with Baldwin the following year, he was re-appointed "bailli" and was given possession of Beirut. Baldwin came to an agreement with Raymond and the Haute Cour to make Baldwin of Montferrat, Sibylla's son by her first marriage, his heir, before Sibylla and Guy. The child was crowned co-king as Baldwin V in 1183 in a ceremony presided by Raymond. It was agreed that, should the boy die during his minority, the regency would pass to "the most rightful heirs" until his kinsmen – the Kings of