William Wellesley-Pole, 3rd Earl of Mornington (1763–1845) was a British politician and an elder brother of the Duke of Wellington.

Career

He was educated at Eton (1774–1776) before entering the Royal Navy, where he served between 1778 and 1782. A Tory, he was Member of Parliament for Trim (1783–1790), East Looe (1790–1795) and Queen's County (1801–1821). He was Chief Secretary for Ireland between 1809 and 1812. He served in Lord Liverpool's government from 1814 to 1823 as Master of the Mint. In 1821 he was elevated to the House of Lords as Baron Maryborough. From 1834 to 1835 he was Postmaster-General. On the death of his elder brother, the Marquess Wellesley, in 1842 he succeeded to the earldom of Mornington.

Family

He was born as William Wesley, but added Pole upon inheriting his cousin's estates in 1781. In 1789 he legally changed his name to Wellesley-Pole. Lord Mornington had three daughters and one son, the last of whom inherited his titles on his death in 1845.

|- style="text-align: center;" | width="30%" |Preceded by:
The Earl of Clancarty | width="40%" style="text-align: center;" |Master of the Mint
1814–1823 | width="30%" |Succeeded by:
George Tierney

|- style="text-align: center;" | width="30%" |Preceded by:
The Marquess Cornwallis | width="40%" style="text-align: center;" |Master of the Buckhounds
1823–1830 | width="30%" |Succeeded by:
The Viscount Anson

|- style="text-align: center;" | width="30%" |Preceded by:
The Marquess Conyngham | width="40%" style="text-align: center;" |Postmaster General
1834–1835 | width="30%" |Succeeded by:
The Marquess Conyngham