The term "Napoleon cannons" refers to a type of artillery known as the Napoleon 12-pounder. Developed in the early 19th century, these cannons were widely used during the American Civil War and other conflicts. They were designed to fire a 12-pound projectile and were known for their accuracy and range, making them effective on the battlefield. Named after Napoleon Bonaparte, these cannons were a significant advancement in military technology. Their smoothbore design allowed for quick loading and firing, and they could be used for both explosive shells and solid shot. The Napoleon 12-pounder became a standard piece of artillery for many armies during its time.