On 21 July 1618 he obtained from the king a charter of the barony of Dalhousie and of the lands of Kerington, Midlothian (Reg.
He succeeded his father in 1629, and on the occasion of the coronation of Charles I in Scotland was admitted to the dignity of Earl of Dalhousie and Lord Ramsay of Kerington by patent dated 29 June 1633 to him and his heirs male.
[2] Dalhousie was among those of the commissioners appointed for the subscription of the king's covenant who were Covenanters; and he subscribed the libel against the bishops presented the same year to the presbytery of Edinburgh.
[2] At the parliament held at Edinburgh in November 1641 Dalhousie's name was inserted in the new list of privy councillors, to displace others chosen by the king.
On 2 August 1645 Montrose's second son James, Lord Graham, who had been confined in Edinburgh Castle, was placed with Dalhousie to be educated.
On 4 May 1648 he was nominated colonel of horse for Midlothian, for the engagement in behalf of Charles I; but apparently did not accept the office, remaining a close partisan of Argyll.