In 1614, Wentworth inherited from an aunt the estate of Toddington, Bedfordshire, until then the property of the Cheyney family, and here he made his principal residence. In 1626, he was created Earl of Cleveland, and in the following year he served under George Villiers, 1st Duke of Buckingham, in the expedition to La Rochelle. Adhering to the cause of King Charles I in the King's dispute with the Parliament of England, he attended his kinsman Thomas Wentworth, 1st Earl of Strafford, at his execution, and afterwards was a general on the royalist side in the Civil War until he was taken prisoner at the Second Battle of Newbury in 1644. Cleveland commanded a cavalry regiment at the Battle of Worcester in 1651, when he was again taken prisoner, and he remained in the Tower of London until 1656.