 In 1624 and again in 1625, 1626 and 1628 Fenwick was elected Member of Parliament for Northumberland.He was created 1st Baronet Fenwick of Fenwick, on 9 June 1628.He was a successful racehorse breeder and became a favourite of Charles I for whom he acted as Master of the Royal Stud at Tutbury and, from 1639, Surveyor of the Royal Race (or Stud).