ST. LEGER, Arthur Mohun, 3rd Visct. Doneraile [I] (1718-50).

Published in The History of Parliament: the House of Commons 1715-1754, ed. R. Sedgwick, 1970
Available from Boydell and Brewer



1741 - 1747
17 Dec. 1747 - Aug. 1750

Family and Education

b. 7 Aug. 1718, o. surv. s. of Arthur St. Leger, 2nd Visct. Doneraile [I], by his 1st w. Mary, da. and h. of Charles, 4th Baron Mohun of Okehampton. m. (1) 3 Apr. 1738, Mary (d. 11 Aug. 1738), da. and h. of Anthony Sheppard of Newcastle, co. Longford, s.p.; (2) 3 June 1739, Catherine, da. of Clotworthy Skeffington, 4th Visct. Massereene [I], s.p. suc. fa. 13 Mar. 1734.

Offices Held

Ld. of the bedchamber to Prince of Wales 1747-d.


‘A young man of great parts, but of no steadiness in courage, conduct, or principles’,1 Doneraile was returned in 1741 by the Government for Winchelsea. When a petition was presented against him he

spoke as well as ever anyone spoke in his own defence, insisted on the petition being heard [at the bar of the House], and concluded with declaring that his cause was his defence and impartiality must be his support.

He then agreed with the Opposition that if they would promise to withdraw the petition he would vote for them on the Westminster election.

His friends reproached him so strongly with his meanness that he was shocked, and went to Mr. Pulteney to get off; Mr. Pulteney told him he had given him his honour and he would not release him, though Lord Doneraile declared it was against his conscience.

In the end he voted with the Opposition on the Westminster petition. In spite of promising to vote straight in future, he ratted once more on the Chippenham election petition,2 the loss of which by only one vote led to Walpole’s resignation.

After Walpole’s fall, Doneraile supported the Government till the Pelhams replaced the Bath-Granville section of the Administration by the leaders of the Opposition at the end of 1744. He then reverted to opposition, distinguishing himself by his skilful attempts to stir up trouble between the old corps of Whigs and their new allies.3 During the rebellion of 1745 he made an effective attack on the Government’s mis-management of the scheme for authorizing some noblemen to raise regiments at their own expense. In 1746 he voted for the Hanoverians as a follower of the Prince of Wales, who made him a lord of his bedchamber in April 1747.

Doneraile was defeated at Winchelsea in the general election of 1747, but was returned for Old Sarum at a by-election by the Prince’s election manager, Thomas Pitt. He disappointed Frederick by not speaking oftener in the House of Commons,4 possibly owing to the consumption which carried him off in Lisbon, August 1750.

Ref Volumes: 1715-1754

Author: Romney R. Sedgwick


  • 1. Walpole, Mems. Geo. II, i. 747 and n.
  • 2. Walpole to Mann, 24 Dec. 1741; Coxe, Walpole, iii. 590.
  • 3. Owen, Pelhams, 254, 261.
  • 4. Walpole, Mems. Geo. II, ut supra.