History of Bristol Welsh estate and Robert of Caen became the first Earl of Gloucester, c. 1122. He is believed to have been responsible for completing Bristol castle. In 1135 Henry I died and the Earl of Gloucester rallied to the support of his sister Matilda against Stephen of Blois who had seized the throne on Henry's death. Stephen attempted to lay siege to Robert at Bristol in 1138 but gave up the attempt as the castle appeared impregnable. When Stephen was captured in 1141 he was imprisoned in the castle, but when Robert was captured by Stephen's forces, Matilda was forced to
Henry I of England of the senior clergy in England and Normandy. Henry's only legitimate son and heir, William Adelin, drowned in the "White Ship" disaster of 1120, throwing the royal succession into doubt. Henry took a second wife, Adeliza of Louvain, in the hope of having another son, but their marriage was childless. In response to this, Henry declared his daughter, Empress Matilda, his heir and married her to Geoffrey of Anjou. The relationship between Henry and the couple became strained, and fighting broke out along the border with Anjou. Henry died on 1 December 1135 after a week of illness. Despite his