During the Civil War, Hawley was the colonel of a Royalist cavalry regiment that he raised to serve under Prince Rupert of the Rhine.
He was created a baronet, of Buckland in the County of Somerset, in the Baronetage of England in 1644.
[4] In October 1645, he obtained the Speaker's licence to go into exile with the Prince, and was subsequently compounded for his estates in 1647 by Oliver Cromwell.
He was a captain in the Royal Horse Guards, commanding a troop, between 1661[5] and 1675, and was a keen supporter of the maintenance of a standing army.
From 1669 until his death, Hawley was a Gentleman of the Bedchamber for the Duke of York.