Years before nuclear-powered doomsday submarines—centuries, even—naval submarine warfare was already in its infancy. A far cry from the missile-toting tubes of metal we have today, early submarines were little more than watertight barrels piloted by daring and clever inventors turned sailors. One of the very first was The Turtle, put to work all the way back in the Revolutionary War. Its mission was a failure, but that makes it no less impressive.
As outlined by the Science Channel, the tiny Turtle was the first known combat submarine, armed with a drill and explosives. The plan was to sneak under British ships docked in New York Harbor, drill into their hulls from underneath, and blow them apart. It didn't quite work out, but that wasn't the Turtle's fault.
Obviously, submersible combat still had a long way to go. It wasn't until the Civil War that an American submarine was actually able to sink a ship, and even then it came at the cost of the sub itself. We've come a long way to arrive at a future where subs dive for months at a time, complete with weapons sufficient to ignite the apocalypse. But at least The Turtle never needed a software update.
Source: Science Channel