Gerald Wellesley, 7th Duke of Wellington, KG (21 August 1885 – 4 January 1972), styled Lord Gerald Wellesley between 1900 and 1943, was a British diplomat, soldier, and architect.
Wellesley was the third son of Lord Arthur Wellesley (later 4th Duke of Wellington) and Lady Arthur Wellesley (later Duchess of Wellington, née Kathleen Bulkeley Williams). He was baptised at St Jude's Church of Ireland parish church, Kilmainham, Dublin, on 27 September 1885 . He was educated at Eton.
Wellesley served as a diplomat in the Diplomatic Corps in 1908. He held the office of Third Secretary of the Diplomatic Service between 1910 and 1917, and the office of Second Secretary of the Diplomatic Service between 1917 and 1919. He was invested as a Fellow of the Royal Institute of British Architects in 1921, and as a Fellow of the Royal Society of Arts in 1935, and was Surveyor of the King's Works of Art 1936–1943. He gained the rank of Lieutenant-Colonel in 1939 in the service of the Grenadier Guards. He fought in the Second World War between 1939 and 1945. In 1943, he succeeded his nephew Henry as Duke of Wellington, Earl of Mornington, and Prince of Waterloo.