In this period Dalrymple Hamilton, whose succession to Bargany had been fraught with costly litigation and hopes of a peerage repeatedly dashed, used his considerable political influence as one of the largest landowners in Ayrshire and Haddingtonshire, where he commanded the contributory burgh of North Berwick, to boost his bids for preferment and to safeguard the succession to his estates of his only daughter Henrietta.
The leader of the Grenvillites in the Commons, Charles Williams Wynn, considered Dalrymple Hamilton their ‘one regular recruit’ to the 1820 Parliament, but he was almost perpetually absent.
He did not stand for Parliament again, but maintained privately that, if elected, he would have supported Canning’s ministry.
