[2] Subsequently, he was major-general of foot under Prince Maurice in the west of England, was knighted at Crediton on 27 July 1644, and distinguished himself by his soldierly retreat in the disastrous Battle of Langport.
Clarendon characterises him as fitted 'rather for execution than counsel, a stout man who looked not far before him, yet he had a great companionableness in his nature, which exceedingly prevailed with those who in the intermission of fighting loved to spend their time in jollity and mirth.'
The judges on circuit and sheriff were seized in their beds, and Wagstaffe thought of hanging them as a seasonable example, but was prevented by the opposition of Colonel Penruddock and the country gentlemen.
When they entered Somerset their numbers began to diminish, and the few who remained were taken or dispersed by Captain Unton Croke at South Molton on the night of 14 March.
He survived the Restoration, petitioned for the reversion of an office [which he did not obtain], and received a small grant of some of the late king's goods in 1662.