CADOGAN, William (?1671-1726).

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



1705 - 16 Mar. 1714
24 Mar. 1714 - 21 June 1716

Family and Education

b. ?1671, 1st s. of Henry Cadogan, counsellor-at-law, of Liscarton, co. Meath by Bridget, da. of Sir Hardress Waller, M.P., of Castletown, co. Limerick; bro. Charles Cadogan. educ. Trinity, Dublin 28 Mar. 1687, aged 15. m. c.1703,1 Margaretta Cecilia, da. of William Munter, councillor of supreme court of Holland, and niece of Adam Tripp, burgomaster regent of Amsterdam, 2da. suc. fa. 1715; cr. Baron Cadogan of Reading 21 June 1716; Earl Cadogan 8 May 1718; K.T. 22 June 1716.

Offices Held

Col. 1694; q.m.g. in Netherlands 1702; col. 7 Horse 1703-12; brig.-gen. 1704; maj.-gen. 1706; lt. Tower of London 1706-12; lt.-gen. 1709; gen. of artillery in Imperial army 1713-14; col. 2 Ft. Gds. 1714-22; gov. Isle of Wight 1715-d.; gen. 1717; col. 1 Ft. Gds. 1722-d.; master-gen. of the Ordnance 1722-5.

Envoy to Hanover 1706, to The Hague 1707-10; master of the robes 1714-d.; ambassador to The Hague 1714-16, 1716-20; P.C. 30 Mar. 1717; one of lords justices 1723.

High steward, Reading 1716-d.


Cadogan was Marlborough’s right-hand man during the war of the Spanish succession, acting not only as his chief of staff and quartermaster but as his personal representative in the House of Commons, where he sat for Woodstock on Marlborough’s nomination. He spoke in favour of the impeachment of Lords Strafford and Oxford in the summer of 1715. Accredited to The Hague to negotiate a barrier treaty, he arranged the transport of 6,000 Dutch troops to Scotland during the rebellion of 1715, serving as second-in-command to the Duke of Argyll, whom he later succeeded. Rewarded with a peerage, he took an active part in the overthrow of Townshend and Walpole, which was attributed to ‘the Marlborough faction, that is, Sunderland, Stanhope, and Cadogan’.2 He was the object of the first full dress attack staged by the new Whig Opposition on 4 June 1717, when Walpole and Pulteney charged him with fraud and embezzlement over the transport of the Dutch troops in a debate in which the ministerial majority fell to ten.

On Marlborough’s death in 1722 Cadogan succeeded him as master-general of the Ordnance, or head of the army, which in effect he had been since Marlborough’s first paralytic stroke in 1716. In 1724 the French ambassador reported that

the immense wealth he has acquired, and his having, by means of the powerful influence of the Duke of Marlborough, passed over the head of many of his seniors in the army, have drawn on him a great many enemies.

He owed his appointment to his favour with the King, who resisted the attempts of the new heads of the Government, Townshend and Walpole, to remove him, till 1725, when he was replaced by the Duke of Argyll. During his last years he became involved in litigation with Marlborough’s widow over £50,000 which the Duke, at the time of his exile, had entrusted to him to invest in the Dutch funds. Cadogan had transferred this sum from the Dutch funds bearing 2½% interest to loans of the Empire at 8%. Claiming that he had profited substantially by the difference in interest, she won her action for damages.3

He died 17 July 1726.

Ref Volumes: 1715-1754

Author: Eveline Cruickshanks


  • 1. Saint Simon, Mems. (ed. Boislisle) xxxiv. 87.
  • 2. HMC Stuart, iii. 447.
  • 3. Coxe, Walpole, ii. 304; Churchill, Marlborough, iv. 641.