Major Patrick Ferguson (1744 – 7 October 1780) was a British Army officer who designed the Ferguson rifle. He is best known for his service in the 1780 military campaign of Charles Cornwallis during the American Revolutionary War in the Carolinas, in which he played a great effort in recruiting American Loyalists to serve in his militia against the Patriots.

Ultimately, his activities and military actions led to a Patriot militia force mustered to put an end to his force of Loyalists, and he was killed in the Battle of Kings Mountain, at the border between the colonies of North Carolina and South Carolina. Leading a group of Loyalists whom he had recruited, he was the only regular army officer participating on either side of the conflict. The victorious Patriot forces desecrated his body in the aftermath of the battle.

Patrick Ferguson was born at Pitfour in Aberdeenshire, Scotland, on 25 May (Old Style)/4 June (New Style) 1744, the second son and fourth child of advocate James Ferguson of Pitfour (who was raised to the judges' bench as a Senator of the College of Justice, so known as Lord Pitfour after 1764) and his wife Anne Murray, a sister of the literary patron Patrick Murray, 5th Lord Elibank.

Through his parents, he knew a number of major figures in the Scottish Enlightenment, including philosopher and historian David Hume, on whose recommendation he read Samuel Richardson's novel Clarissa when he was fifteen, and the dramatist John Home. He had numerous first cousins through his mother's family: these included Sir William Pulteney, 5th Baronet, Commodore George Johnstone, and Sir James Murray (later Murray-Pulteney).

Ferguson began his military career in his teens, encouraged by his maternal uncle James Murray. He served briefly in the Holy Roman Empire with the Scots Greys during the Seven Years' War, until a leg ailment – probably tuberculosis in the knee – forced him to return home. After recovering, now in peace-time, he served with his regiment on garrison duty. In 1768, he purchased a command of a company in 70th Regiment of Foot, under the Colonelcy of his cousin Alexander Johnstone, and served with them in the West Indies until his lame leg again began to trouble him. In 1770, Ferguson purchased the Castara slave plantation in Tobago. After Ferguson's death, the plantation was inherited by his younger brother George, who had managed it since the early 1770s and developed it into a successful enterprise. Exports of rum, sugar, and molasses were sent back to Europe from it. After returning home in 1772, he took part in light infantry training, coming to the attention of General Howe. During this time, he developed the Ferguson rifle, a breech-loading flintlock weapon based on Chaumette's earlier system.

In 1777, Ferguson went to the colonies to serve in the American War of Independence; commanding an experimental rifle corps equipped with his new rifle. However, after initial success, he was shot through the right elbow joint at the Battle of Brandywine on 11 September 1777 in Pennsylvania. Shortly before, he had had the chance to shoot a prominent American officer, accompanied by another in distinctive hussar dress, but decided not to do so, as the man had his back to him and was unaware of Ferguson's presence. A surgeon told Ferguson in the hospital that some American casualties had said that General Washington had been in the area at the time. Ferguson wrote that, even if the officer were the general, he did not regret his decision. The officer's identity remains uncertain; historians suggest that the aide in hussar dress might indicate the senior officer was Count Casimir Pulaski. For some months after being wounded, Ferguson was at risk of having his arm amputated. During this time, he received news of his father's death. Ferguson eventually recovered, although his right arm was permanently crippled.

Ferguson resumed his military duties in May 1778, under the command of Sir Henry Clinton.

In October 1778, Ferguson was assigned to lead a raid in southern New Jersey to suppress privateers who had been seizing British ships. They were based around the Little Egg Harbor River, which empties into the Great Bay. Ferguson attacked their base in what is known as the Battle of Chestnut Neck.