In the 14th century, Limerick was an important port for the English Crown. To guard access via the Shannon estuary against attacks from the Irish, the site was once again occupied. In 1353, Sir Thomas de Rokeby led an English army to conquer the MacNamaras and MacCarthys. A new castle (the third) was built at Bunratty, but once again, its exact location is unknown. Local tradition holds that it stood at the site where the Bunratty Castle Hotel was later constructed. However, the new structure was hardly finished before being captured by the Irish. Documents show that in 1355, King Edward III of England released Thomas Fitzjohn Fitzmaurice from prison in Limerick. He had been charged with letting the castle fall into the hands of Murtough O’Brien whilst serving as a Governor (Captain) of Bunratty.