It was granted its first charter in 1155 by Henry II. In 1216 Henry III, aged only ten years, was crowned with a gilded iron ring in the Chapter House of Gloucester Cathedral. Gloucester's significance in the Middle Ages is underlined by the fact that it had a number of monastic establishments, including St Peter's Abbey founded in 679 (later Gloucester Cathedral), the nearby St Oswald's Priory, Gloucester founded in the 880s or 890s, and Llanthony Secunda Priory, founded 1136. The town is also the site of the Siege of Gloucester in 1643, during which the city held out against Royalist forces in the First English Civil War.