In 1747-1748 he was again with the duke of Cumberland in the Low Countries, and in 1749 was transferred to the cavalry, receiving the colonelcy of the 7th (3rd) Irish Horse (Carabineers).
In 1770 Granby, worn out by political and financial trouble, resigned all his offices, except the colonelcy of the Blues.
In 1753 he was given the colonelcy of the 14th foot, and in 1754 he became a major-general.
Mr Roosevelt declined the colonelcy of the regiment, preferring to take the post of lieutenant-colonel under his intimate friend Dr Leonard Wood, who, while a surgeon in the United States army, had served in action with gallantry and skill against the Indians.
In 1636 he entered parliament as member for Stafford, and during the Civil War held a colonelcy in the parliamentary army.
He won his colonelcy by his ability and valour at the battles of Alibunar and Lagerdorf in 1848.
He commanded his regiment at the battles of Talavera and Busaco, and in 1810 received a colonelcy and the appointment of A.D.C. to the king.
He was given the colonelcy of the 10th (Lancashire Fusiliers), but was too late to take part in the battle of Culloden.