Queen of Jerusalem (1113-1117) as third wife of King Baldwin I.
Born around 1075, Adelaide was a daughter of Manfred del Vasto (d. 1079), a member of the Aleramid dynasty of Liguria. After the death of her first husband, Count Roger I of Sicily (1101), she acted as regent for their sons Simon (d. 1105) and Roger II. In September 1113 she married Baldwin I of Jerusalem; the marriage brought a large cash dowry, but was contracted under the condition that if it produced no heirs, the kingdom of Jerusalem was to pass to Roger II on Baldwin’s death. With no heir having been born by the winter of 1116-1117, a serious illness of Baldwin raised the prospect of a Sicilian succession, and a section among the kingdom’s ruling class, led by the Patriarch Arnulf, forced the king to repudiate Adelaide, a move made easier by the fact that his second wife was still living. Adelaide returned to Sicily in April 1117, and died on 16 April 1118.