William Courtenay, 10th Earl of Devon

William Courtenay (19 June 1777 – 19 March 1859) was an English politician, M.P. for Exeter from 1812 until 1826. He succeeded to the title of Earl of Devon in 1835.

He was born on 19 June 1777, the eldest son of Henry Reginald Courtenay, Bishop of Exeter, and wife Lady Elizabeth Howard, daughter of Thomas Howard, 2nd Earl of Effingham. He was educated at Westminster School and Christ Church, Oxford. He was called to the bar at Lincoln's Inn in 1799, and was, for some time, a Master of Chancery.

He was Member of Parliament for Exeter from 1812 until January 1826, when he resigned his seat following his appointment as clerk-assistant to the House of Lords, at an annual salary of £4,000. He held the post until May 1835, when he succeeded his second cousin as 10th Earl of Devon, inheriting Powderham Castle in Devon and estates in Ireland. He was elected High Steward of Oxford University in 1838, and was a governor of the Charterhouse.

In 1843, British Prime Minister, Sir Robert Peel, appointed him chairman of a commission to investigate the Irish land question. The resulting report by the Devon Commission was published in 1845.

He died at Shrivenham, Berkshire, at the house of his brother-in-law, on 19 March 1859.

Courtenay played cricket for MCC in the 1790s. He is recorded in one first-class match in 1797, totalling 1 run with a highest score of 1.

Courtney was married twice. He was succeeded as Earl of Devon by his eldest son, also named William. His fourth son, Charles Leslie Courtenay was a Canon of Windsor from 1859 until 1894.