Grimston was admitted to Lincoln's Inn in 1767. He became Member of Parliament for St Albans in 1784, filling the place of his brother James (who, as an Irish peer, could sit in the House of Commons); James Grimston withdrew as a candidate on polling day and William took the seat. He generally supported the ministry. In the 1790 general election, he stepped aside, in favour of John Calvert. In 1791 he was elected again, for Appleby, remaining in parliament to 1795.[1]
On 21 January 1797, Grimston changed his surname to Bucknall, fulfilling a condition in the will of his uncle John Askell Bucknall. He died on 25 April 1814.[3][4]
Family
Grimston married in 1783 Sophia Hoare, daughter of Richard Hoare of Boreham, Essex, a banker and grandson of Richard Hoare (1648–1719), and of Susanna Cecilia Dingley (1743–1795). They had a daughter, Sophia Askell (1784–1859), who had a court position as woman of the bedchamber to Adelaide of Saxe-Meiningen. She married in 1804 the Honorable Berkeley Paget, a younger son of Henry Paget, 1st Earl of Uxbridge, by whom she had seven children. The other child of the marriage, John, died an infant.[4][5][6]