sentences:  Its presence caused great consternation in Gloucester until a Parliamentarian army commanded by Sir William Waller defeated it on 24 March.The defeat of Waller in the Battle of Roundway Down on 13 July by the Royalist Western Army left both Bristol and Gloucester vulnerable, and on 18 July Rupert led another Royalist army out of Oxford to take control of the Severn valley.On 26 July Rupert's Oxford Army, supported by the Western Army, seized Bristol.