The title of Duke of Wellington and Marquess of Douro was bestowed upon Arthur Wellesley, 1st Marquess of Wellington on May 11, 1814.

Arthur Wellesley was born Arthur Wesley May 1, 1769 son of Garret Wesley, Earl of Mornington in Dublin in Ireland. He adopted the spelling Wellesley in about May of 1798.

The subsidiary titles of the Duke of Wellington are: Marquess of Wellington (1809), Marquess of Douro (1814), Earl of Mornington (1760), Earl of Wellington (1812), Viscount Wellesley (1760), Viscount Wellington of Talavera and Wellington (1809), Baron Mornington (1746) and Baron Douro (1809). The Viscounty of Wellesley and the Barony and Earldom of Mornington are in the Peerage of Ireland; the remaining are in the Peerage of the United Kingdom.

Dukes of Wellington (1814)

• Arthur Wellesley, 1st Duke of Wellington (1769-1852)
• Arthur Richard Wellesley, 2nd Duke of Wellington (1807-1884)
• Henry Wellesley, 3rd Duke of Wellington (1846-1900)
• Arthur Charles Wellesley, 4th Duke of Wellington (1849-1934)
• Arthur Charles Wellesley, 5th Duke of Wellington (1876-1941)
• Henry Valerian George Wellesley, 6th Duke of Wellington (1912-1943)
• Gerald Wellesley, 7th Duke of Wellington (1885-1972)
• Arthur Valerian Wellesley, 8th Duke of Wellington (b. 1915)

The current heir to the title is the 8th Duke's son currently styled Arthur Charles Valerian Wellesley, Marquess of Douro.