Granville Leveson-Gower, 1st Earl Granville GCB PC (12 October 1773 – 8 January 1846), known as Lord Granville Leveson-Gower from 1786 to 1814 and as the Viscount Granville from 1814 to 1833, was a British Whig statesman and diplomat.

Granville was a son of Granville Leveson-Gower, 1st Marquess of Stafford and his third wife Lady Susannah Stewart, daughter of Alexander Stewart, 6th Earl of Galloway. He was also a younger, paternal half-brother of George Leveson-Gower, 1st Duke of Sutherland. He was educated at Dr Kyle’s school at Hammersmith, and then by the Revd John Chappel Woodhouse, before matriculating at Christ Church, Oxford, in April 1789. He took no degree, but became a DCL in 1799.

Political and Diplomatic Career
He served as British ambassador to Russia (10 August 1804 – 28 November 1805 and 1806–1807) and France (1824–1828, 1830–1835, 1835–1841). In 1815 he was raised to the peerage as Viscount Granville, of Stone Park in the County of Stafford. In 1833, he was further honoured when he was created Baron Leveson, of Stone Park in the County of Stafford, and Earl Granville.

Family
Lord Granville married Lady Harriet Cavendish (1785–1862), daughter of William Cavendish, 5th Duke of Devonshire and Lady Georgiana Spencer, in 1809. They had two sons and two daughters. Their eldest son, Granville Leveson-Gower, 2nd Earl Granville, became a distinguished politician. Their second son the Hon. Frederick Leveson-Gower was also a politician. Their daughter Lady Georgiana married Alexander Fullerton. She was a biographer, novelist, and great philanthropist. Lord Granville died in January 1846, aged 72. The Countess Granville died in November 1862, aged 77. Lord Granville, prior to marrying Lady Harriet Cavendish, was the lover of Lady Harriet’s maternal aunt, Henrietta Ponsonby, Countess of Bessborough, née Lady Henrietta Frances Spencer, with whom he fathered two illegitimate children: Harriette Stewart and George Stewart.