Crazy enough the submarine was invented during the renaissance! Leonardo Da Vinci first invented it but he kept it a secret because he didn't want to make war worst. The first person to make the submarine was Cornelius Drebbel. in 1620 A.D. this Dutch inventor made a row boat with a leather covering and watertight seals. Up to 12 people could fit in it and also Drebbel was an inventor for the British navy. His submarine could only go down 15 feet for two hours so it wasn't that efficient. The submarine changed war as well. Soldiers could now go underwater without taking on fire from the land.