National Submarine Day Date in the current year: April 11, 2024

Submarines are watercraft capable of prolonged independent operation underwater. They are different from submersibles, underwater vehicles that are not self-supportive and need to be transported and supported by a larger watercraft or platform.

People have been attempting to find methods to travel underwater since ancient times. According to legends, Alexander the Great used primitive submersibles during the siege of Tyre in 332 BC, although Aristotle recounts that he used divers.

During the Middle Ages, scientists created various plans for submersibles or submarines, but the first navigable prototype submarine was designed by English mathematician William Bourne, who published his submarine design in his book Invention of Devices in 1578. By the mid-18th century, more than a dozen patents for submersibles and submarines had been granted in the United Kingdom.

The first military submersible to be used in combat was built in the United States in 1775. Named Turtle, it was used by the Continental Army to attach explosives to the undersides of Royal Navy ships in New York Harbor during the American Revolutionary War.

The first modern submarines were developed around the world in the late 19th century thanks to the advent of the electric battery technology. Polish engineer Stefan Drzewiecki built the first electrically powered submarine in 1881 while working in Russia. Other European engineers later used his design in their electric submarines.

Navies began to put submarines to service at the turn of the 20th century. The first modern commissioned submarine in the United States Navy was Holland VI, later renamed USS Holland. It was designed and built under the supervision of Irish engineer John Philip Holland in 1896–1897. The submarine was launched on May 17, 1897 and acquired by the US government for the United States Navy on April 11, 1900.

The submarine underwent a number of modifications after christening and was commissioned on October 12, 1900, with Lieutenant Harry Handly Caldwell in command. Caldwell thus became the world’s first naval submarine commanding officer.

The history of National Submarine Day goes back to 1969, when Senator Thomas J. Dodd introduced a bill to the United States Senate to designate April 11 as National Submarine Day. The bill passed the Senate and was introduced to the House of Representatives, but it was never signed by President Richard Nixon.

Despite the lack of presidential proclamation, National Submarine Day has been observed since 1970 by the United States Navy service members and veterans, as well as by various relevant organizations. You can join the celebration by reading articles or watching a documentary about submarines, listening to “Yellow Submarine” by the Beatles, visiting a submarine museum (there are several dozen submarines on display in the United States), and spreading the word on social media with the hashtag #NationalSubmarineDay.