Born in Ireland, the younger son of Garret Wesley, 1st Earl of Mornington
Young Wellesley entered army in 1787, where he rose rapidly in rank and soon held a command in Flanders. During this time he was also elected as an Irish Member of Parliament (in 1790), which position he held until 1797.
In 1796 he went with his division to India. The next year, his elder brother Richard was appointed governor general of India, and when war broke out in 1799 against the Sultan of Mysore?, Tipu Sultan, Arthur commanded a division of his own. Following the successful conclusion of that campaign, Arthur was appointed to the supreme military and political command in the Deccan; while in that position he defeated the robber chieftan Dhundia Wagh (1802) and the Marathas? (in 1803). When his brother's term was up in 1805, he returned with him to England, and was knighted. He was re-elected as an MP in 1806, and was appointed Irish Secretary in 1809.
It was in the years following his return to England that the younger Wellesley undertook the events that made his place in history. Since 1789, France had been embroiled in the French Revolution, and Napoleon Bonaparte had reached the heights of power in Europe. The British government was casting about for ways to end Napoleon's threat to them, and Wellesley began to supply it to them.
First came an expedition to Denmark in 1807, which soon led to Wellesley's appointment as Lieutenant General in the [Peninsular War]?. Though that war wasn't going particularly well, it was the one place where the British (and the Portuguese) had managed to put up a fight on the European mainland against France and her allies. He defeated the French at the [Battle of Roliça]? and the [Battle of Vimeiro]? in 1808. The resulting [Convention of Cintra]? (the French pulled out of Lisbon, but their army was repatriated on British ships) was controversial, and Wellesley was briefly recalled to Britain. In the meantime, however, Napoleon himself had come to Spain, and when the chief commander [Sir John Moore]? died, Wellesley was given his position.
Returning to Iberia in April 1809, he defeated the army of King Joseph (Bonaparte) of Spain at the [Battle of Talavera]? in 1809, then drove French forces out of Portugal entirely in 1810-11. Driving into Spain he defeated the French again the [Battle of Salamanca]?, then took Madrid in 1812. A French counter-attack put British forces in a precarious position, but Wellesley was given command of all allied armies in Spain. A new offensive in 1813, culminating in the [Battle of Vitoria]? pushed French forces back across the border with France. A follow-up invasion of southern France had reached Toulouse? when Napoleon abdicated for the first time on 12 April 1814.
Returning to England hailed as the conquering hero, Wellesley was appointed Duke of Wellington, a title his descendants hold to this day. He was soon appointed ambassador to France, then took [Viscount Castlereagh]?'s place at the [Congress of Vienna]?, where he strongly advocated allowing France to keep its place in the European balance of power.
On February 26 1815, Napoleon left his exile on Elba? and returned to France. Gaining control once again over the country by May, he then faced a reformation of the alliance against him. Wellington left Vienna to command the British forces. He ended up in Belgium, along with Prussian forces under [Gebhard Leberecht von Blücher]?, where after a complicated series of events the joined armies finally defeated Napoleon at the Battle of Waterloo. The French Emperor abdicated once again on June 22, and was spirited away by the British to distant St. Helena.
(Political career to follow)
A query: Brittanica & several other on-line sources say May 1 1769 for his birthday