Battles & Wars › Revolutions & Napoleon › American Revolutionary War
Submarine
Turtle 1775; Hunley sinks a warship 1864; U-boats 1914· Invention or discovery· Weapons, armor & warships
Well documentedSolid records, physical evidence or scientific consensus.
A warship that hides underwater: from a one-man wooden craft in 1776 to the diesel-electric U-boats of World War I.
See it on the Battles & Wars map →What happened
David Bushnell's Turtle (1775) was a hand-cranked wooden shell for one man, meant to screw a gunpowder charge to an enemy hull. In 1864 the Confederate H. L. Hunley, cranked by eight men, became the first submarine to sink a warship, and sank too. Practical submarines needed propulsion that worked underwater and a weapon with reach: electric batteries, diesel engines and the self-propelled torpedo (1866). John Holland's designs, bought by the US Navy in 1900, set the pattern.
Why it matters
Submarines let weaker navies threaten stronger ones and nearly starved Britain in both world wars. Nuclear-missile submarines later became the hardest-to-destroy part of nuclear deterrence.
How we know
Bushnell's letters and his pilot's account, navy records, and the Hunley's wreck, found in 1995 and raised in 2000; 20th-century naval archives are extensive.
Still debated
Who deserves credit for the first submarine is argued: Cornelis Drebbel's 1620s boat on the Thames is thinly documented, and Holland, Simon Lake and France's Maxime Laubeuf rivaled each other around 1900.
Inside this (1)
Connections (5)
▸Submarine made the first submarine attack (1776) in the American Revolutionary WarWell documented
The connection
Bushnell's Turtle was built to break the British fleet's hold on New York Harbor. On September 7, 1776, Sergeant Ezra Lee cranked it under Admiral Howe's flagship, HMS Eagle, but could not attach the gunpowder charge to the hull. He released it as he escaped, and it exploded harmlessly.
When and how
New York Harbor, September 1776; inventor David Bushnell, a Yale-educated Connecticut man, and pilot Ezra Lee.
How we know
Lee's later account, Bushnell's 1787 letter to Thomas Jefferson, and George Washington's praise of the effort; British records do not mention the attack.
Debates and open questions
With no British record, some historians doubt it happened as described; why the screw failed, copper sheathing or poor control, is unknown.
▸Submarine sank its first warship (Hunley, 1864) in the American Civil WarWell documented
The connection
The Confederacy, facing a far stronger navy, backed underwater craft. On February 17, 1864, the hand-cranked H. L. Hunley drove a spar-mounted torpedo into USS Housatonic off Charleston, sinking her; five Union sailors died. The Hunley never returned, the third crew it lost, but it proved a submarine could sink a warship.
When and how
Off Charleston, South Carolina, February 17, 1864; the Hunley's crew of eight under Lieutenant George Dixon, against the Union blockade.
How we know
Union reports of the sinking, and the Hunley's wreck, found in 1995 and raised in 2000 with its crew's remains, now studied in North Charleston.
Debates and open questions
Why the Hunley sank after its attack is still debated; one study argues the blast wave of its own torpedo killed the crew instantly.
▸Submarine made possible U-boats and unrestricted submarine warfareWell documented
The connection
By 1914 diesel-electric submarines with self-propelled torpedoes could cruise far out to sea. On September 22, 1914, Germany's U-9 sank three British cruisers in about an hour, killing some 1,450 men. Germany then turned U-boats against merchant shipping, sinking roughly 5,000 ships during the war and nearly starving Britain in 1917.
When and how
North Sea and Atlantic, 1914–18; Germany's U-boat fleet against British, Allied and neutral shipping.
How we know
Admiralty and German naval records, ship-loss lists compiled after the war, and wrecks on the seabed.
Debates and open questions
Whether a U-boat campaign launched earlier and with more boats could have won the war for Germany is debated.
▸Submarine was transformed by nuclear power into the Nuclear and missile submarines (Nautilus, Polaris)Well documented
The connection
Diesel-electric submarines of both World Wars spent much of their time surfaced and crept slowly on batteries underwater. A nuclear reactor removed that limit: needing no air, boats like Nautilus could stay submerged for weeks at high speed, turning the submarine from a diving torpedo boat into a true underwater warship.
When and how
Groton, Connecticut, where Electric Boat built Nautilus (launched January 1954); Admiral Hyman Rickover led the Navy's reactor program.
How we know
Navy records and Nautilus's own voyages of 1955–58, including the first submerged passage under the North Pole, demonstrate the change.
Debates and open questions
Some navies still prefer cheaper diesel-electric or air-independent boats, which near coasts can be as quiet as nuclear submarines.
▸Electric Boat (later General Dynamics) sold the US Navy its first modern SubmarineWell documented
The connection
Irish-born teacher John Philip Holland spent decades designing submarines in the US. His Holland VI used a gasoline engine on the surface and batteries underwater, with diving planes and a torpedo tube, the basic layout of submarines until nuclear power. Electric Boat sold it to the Navy in 1900 for $150,000 as USS Holland, and sold the design abroad.
When and how
Elizabeth, New Jersey, launched 1897; bought by the US Navy April 11, 1900; Holland and Isaac Rice. Britain, Japan and Russia bought Holland-type boats.
How we know
Navy purchase records, trial reports and ship histories, and the Holland design licensed to Vickers in Britain.
Debates and open questions
Whether Holland or his rival Simon Lake deserves more credit is argued, and Holland left the company in 1904 after disputes.