In 1140 Lincoln the city and castle were taken possession supporters of Matilda, the daughter of King Henry I. Matilda was fighting to take the English throne from King Stephen. The King's army besieged the castle in the final months of 1140 and when news reached Matilda she sent her army to help. In February 1141 at the Battle of Lincoln King Stephen was captured and transported to Bristol where he was held prisoner for a short time.
At the start of the Civil War, in the reign of Charles I, the castle was fortified and held by Royalist supporters. But the castle and the city fell to Parliamentarian forces in May 1644.