1776 World's first submarine attack: the American submersible craft ''Turtle'' attempts to attach a time bomb to the hull of British Admiral Richard Howe's flagship HMS ''Eagle'' in New York Harbor.
1863 American Civil War: The ''H. L. Hunley'', the first submarine to sink a ship, sinks during a test, killing its inventor, Horace L. Hunley.
1864 American Civil War: The {{Ship||H. L. Hunley|submarine|6}} becomes the first submarine to engage and sink a warship, the {{USS|Housatonic|1861|6}}.
1912 In Groton, Connecticut, the first diesel-powered submarine is commissioned.
1915 World War I: German submarine {{SMU|U-20}} sinks {{RMS|Lusitania}}, killing 1,198 people including 128 Americans. Public reaction to the sinking turns many formerly pro-Germans in the United States against the German Empire.
1915 US Navy salvage divers raise F-4, the first U.S. submarine sunk in accident.
1917 World War I: The United States breaks off diplomatic relations with Germany a day after the latter announced a new policy of unrestricted submarine warfare.
1918 A series of accidental collisions on a misty Scottish night leads to the loss of two Royal Navy submarines with over a hundred lives, and damage to another five British warships.
1930 The United Kingdom, Japan and the United States sign the London Naval Treaty regulating submarine warfare and limiting shipbuilding.
1939 The U.S. Navy submarine USS ''Squalus'' sinks off the coast of New Hampshire during a test dive, causing the death of 24 sailors and two civilian technicians. The remaining 32 sailors and one civilian naval architect are rescued the following day.
1939 The German Kriegsmarine submarine (U-boat) ''U-47'' sinks the British battleship HMS ''Royal Oak'' within her harbor at Scapa Flow, Scotland.
1940 World War II: The German submarine ''U-9'' sinks the French coastal submarine Doris near Den Helder.
1941 For the first time in World War II, a German submarine attacks an American ship.
1942 World War II: A Japanese submarine surfaces near the Columbia River in Oregon, firing 17 shells at nearby Fort Stevens in one of only a handful of attacks by the Japanese against the United States mainland.
1943 A Japanese submarine sinks {{Ship|AHS|Centaur}} off the coast of Queensland.
1943 World War II: The British destroyers {{HMS|Eclipse|H08|6}} and {{HMS|Laforey|G99|6}} sink the Italian submarine ''Ascianghi'' in the Mediterranean after she torpedoes the cruiser {{HMS|Newfoundland|59|6}}.
1944 World War II: A hunter-killer group of the United States Navy captures the German submarine erman submarine U-505|''U-505''
1944 World War II: The British submarine {{HMS|Tradewind}} torpedoes Junyō Maru, 5,600 killed.
1954 The first nuclear-powered submarine, the {{USS|Nautilus|SSN-571|6}}, is launched in Groton, Connecticut by Mamie Eisenhower, the First Lady of the United States.
1954 The U.S. Navy submarine {{USS|Nautilus|SSN-571|6}} is commissioned as the world's first nuclear reactor powered vessel.
1958 The nuclear submarine {{USS|Nautilus|SSN-571|6}} travels beneath the Arctic ice cap.
1959 The {{USS|George Washington|SSBN-598|6}} is launched. It is the first submarine to carry ballistic missiles.
1963 129 people die when the submarine USS ''Thresher'' sinks at sea.
1966 Off the coast of Spain in the Mediterranean, the {{Ship|DSV|Alvin}} submarine finds a missing American hydrogen bomb.
1968 The nuclear-powered submarine the {{USS|Scorpion|SSN-589|6}} sinks with 99 men aboard 400 miles southwest of the Azores.