Muzzleloader
In 1853 France introduced the Canon-obusier de 12, a 12-pounder capable of firing both shot and shell also called a "Napoleon". The U.S. Army adopted the Napoleon 12-pounder in 1857 as the Model 1857 12-Pounder Napoleon Field Gun. It became the most popular field gun on both sides during the American Civil War. They were ultimately replaced by breach-loading cannons after the Civil War.