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
Wars of the Roses reigned for 78 days as Edward V, but was then deposed by his uncle, who became Richard III. The final victory went to a relative and claimant of the Lancastrian party, Henry Tudor, son of Henry VI's half-brother Edmund Earl of Richmond, who defeated Richard III at the Battle of Bosworth Field. After assuming the throne as Henry VII, he married Elizabeth of York, the eldest daughter and heir of Edward IV, thereby uniting the two claims. The House of Tudor ruled the Kingdom of England until 1603, with the death of Elizabeth I, granddaughter of Henry VII and Elizabeth