John Jervis, 1st Earl of St Vincent, English admiral and politician (d. 1823)
John Jervis, 1st Earl of St Vincent (9 January 1735 – 13 March 1823) was a British politician and naval officer. He served as an admiral in the Royal Navy and Member of Parliament throughout the latter half of the 18th century and into the 19th, and was an active commander during the Seven Years' War, American War of Independence, French Revolutionary War and the Napoleonic Wars. He is best known for his victory at the 1797 Battle of Cape Saint Vincent, from which he earned his titles, and as a patron of Horatio Nelson. Despite having a fierce reputation for discipline his crews had great affection for him, calling him Old Jarvie.Jervis was also recognised by both political and military contemporaries as a fine administrator and naval reformer. As Commander-in-chief of the Mediterranean, between 1795 and 1799 he introduced a series of severe standing orders to avert mutiny. He applied those orders to both seamen and officers alike, a policy that made him a controversial figure. He took his disciplinarian system of command with him when he took command of the Channel Fleet in 1799.

In 1801, as First Lord of the Admiralty he introduced a number of reforms that, though unpopular at the time, made the Navy more efficient and more self-sufficient. He introduced innovations including block making machinery at Portsmouth Royal Dockyard. St Vincent was known for his generosity to officers he considered worthy of reward and his swift and often harsh punishment of those he felt deserved it.

Jervis' entry in the Oxford Dictionary of National Biography by P. K. Crimmin describes his contribution to history: "His importance lies in his being the organiser of victories; the creator of well-equipped, highly efficient fleets; and in training a school of officers as professional, energetic, and devoted to the service as himself."