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,
Baldwin I, Latin Emperor trying to seduce Kaloyan's wife. The historian George Acropolites reports that the Tsar had Baldwin's skull made into a drinking cup, just as had happened to Nicephorus I almost four hundred years before. Tsar Kaloyan wrote to Pope Innocent III, reporting that Baldwin had died in prison. A tower of the Tsarevets fortress of the medieval Bulgarian capital, Veliko Tarnovo, is still called Baldwin's Tower; supposedly, it was the tower where he was interned. It was not until July 1206 that the Latins in Constantinople had reliable information that Baldwin was dead. His brother Henry was crowned emperor in August.