Arthur Wellesley, 1st Duke of Wellington, was a celebrated British soldier, well known for his command of the Battle of Waterloo and of the main British army in the second half of the War of 1812. After this, he became a temporary governer of the Occupied Region, though he was replaced in 1820. After this, he and an army helped Spain in the Rebellion of New Spain by the terms of the Wellesley-Onís Treaty, negotiated by himself and Spanish foreign minister Luis de Onís.
After helping in the Rebellion of New Spain, Wellesley returned to England and entered a life of politics, becoming an influential member of the Tory party. He became Prime Minister of the United Kingdom in 1830, keeping the post until 1833. However after this he was still politically active, as he was a minister in the Cabinet.
Interestingy, Wellesley was brother-in-law to British Major-general Edward Pakenham, as he married Pakenham's sister. Pakenham was a successful soldier, if not as successful as Wellesley.