He was active in marching against the rebels and he presided over the parliament of 1536, but he was soon at variance with the powerful family of the Butlers and with some of the privy councillors, including the highly influential John Rawson, 1st Viscount Clontarf.
[3] Grey was nevertheless tried and attainted of high treason, and subsequently executed at the Tower of London on 28 July 1541 by the orders of Henry VIII.
As an active participant in the Tudor conquest of Ireland, he was one of the figures who brought a new element to Irish warfare, where the killing of non-combatants by Crown forces was seen as acceptable by the establishment.
It is the very fact that he included this information in his report to London, deeming it a piece of service fit to be recorded, that pinpoints his significance in the military history of sixteenth-century Ireland.
27 June 1527 Eleanor Sutton, daughter of Edward Sutton, 2nd Baron Dudley by Cecily Willoughby, daughter and coheiress of Sir William Willoughby and widow of Charles Somerset, Earl of Worcester (1460, 15 March 1526): Leonard Grey presented Thomas Mounteforth as rector of Aldwincle All Saints on 27 June 1527 in right of his wife, Countess of Worcester;[8] She died before 24 May 1532, when Leonard Grey was contemplating marriage with Elizabeth, widow of Gilbert, Lord Tailbois, which marriage did not take place.