Arthur Wellesley, first Duke of Wellington (1769-1852), was the fifth but third surviving son of Garret Wesley, first Earl of Mornington, and Anne Hill, daughter of the first Viscount Dungannon. He was educated in Chelsea and briefly at Eton. He was then sent to the military academy in Angers, 1785-6, to prepare him for a career in the army.
When he was eighteen, Wellington received a commission in the Seventy Third Regiment of Foot, and thereafter he moved through the ranks fairly rapidly, becoming a colonel in 1796, and through his demonstrable military prowess, a major general in 1802, a lieutenant general in 1808, a general in 1811 and field marshal in 1813. Wellington was aide-de-camp to two successive Lords Lieutenant of Ireland, the Earl of Westmorland and Earl Fitzwilliam, 1787-1793, and between 1790 and 1797 he sat in the Irish Parliament as Member for the family seat of Trim (MS 61 WP1/1-6).
From 1797 to 1805, Wellington served in India, largely in Mysore and adjacent areas, taking a prominent role both in the campaign against Tipoo Sultan in 1799, at Seringapatam, and during the Anglo-Maratha war of 1803-5, winning notable victories at Assaye and Argaum, and bringing about the submission of Sindhia and of the Raja of Berar (MS 61 WP1/7-163; MS 61 WP3/1-3).
After returning to England, Wellington commanded a brigade in the abortive expedition to recapture Hanover, December 1805 to February 1806. He became Member of Parliament for Rye in 1806, for Mitchell, 1807, and for Newport (Isle of Wight) 1807-9 (MS 61 WP1/164-5).