Submachine-Guns of the CSA.
The first Confederate SMG to enter service would be the M1925 Machine Pistol, a locally made derivative of the C96 Pistol in .45 ACP. They were mainly used by the Confederate Navy and Air Force as well as the Police due to it's compact nature. These would be used until 1958 by the Navy and Air Force and 1959 by the Police when they were fully replaced by the Thompson. This firearm would be significant because it would be first major production gun to be built in the CSA, thus, they would have the reputation of being poorly built.
In 1924, the Confederacy would purchase 25,000 SiG M1920 submachine-guns in 7.63x25mm from SiG to equip the Confederate Army and Navy.
The CSA would also buy 22,000 of the MP-28 II model of Submachine-gun from Haenel in the early 1930s in the same caliber. The M1920s and MP-28 would be used extensively by the Confederacy for military use until the early 1950s when they were supplanted by the Union built Thompson Submachine-Gun. They would remain in use with the Confederate Police until 1959 when they were replaced by the Thompsons and the M1 Carbines.
In 1939, the Confederacy would purchase 10,000 Suomi M/31 Submachine Guns in 9x19mm from Finland as part of the increase of it's Military in the build up to WWII. Unfortunately, as these guns were about to be shipped out of Finland, the USSR would invade Finland and guns intended for the CSA would end up being pressed into service with the Finnish Army during the Winter War and the Continuation War. Some of them would also be used by the Soviet forces as well as the German Wehrmacht and the Independent State of Croatia.
When the Confederate Navy got into their possession the ex-British Light Cruisers Jamaica, Sirius, and Diadem and the Destroyers Cleveland, Cotswold, Farndale, and Racehorse, they subsequently came into possession of many Lanchester Submachine-Guns in 9x19mm Luger. These would be mainly used by the Confederate Coast Guard, Police, and Gendarme until the early 1970s when replaced by the West German built MP-5.
In the years following WWII, the Union would supply to the Confederate Government thousands of Thompson Submachine Guns as Foreign Aid. The Confederate Weapons Arsenal in Atlanta would produce copies known as the M1950 submacine gun in .45 ACP. The Confederate Army and Paratroop Corps would use the type until 1963 when they replaced by the FN FAL rifles. The Navy and Air Force would use their Thompsons until the late 1960s-early 1970s when replaced by the FALs, Uzis, and MP-5s. The Coast Guard would keep theirs until the 1973 when they were replaced by the Israeli made Uzis. The Gendarme would be the final user of the type in the Confederacy, when in 1991, they retired their last Thompsons.
In 1961, the Confederacy would adopt into service the Israeli built Uzi Submachine Gun in .45 ACP. They would become popular with the Confederate Tank Crews and Paratroops due to it's compact nature. The Police, Presidential Guard, Navy, Air Force, Coast Guard, Gendarme, Task Force 7, and the Georgian Knights would too adopt the weapon.
In 1969, the Confederate Government would purchase from H&K 20,000 MP-5 SMGs in .45 ACP for it's Air Force and Police Forces.
One of the derivatives of the MP-5, the MP-5k in 9x19mm, would be mainly used by the Presidential Guard, Task Force 7, and various counter-terrorist units in the CSA.
In 2004, the Confederate Paratroop Corps would adopt the H&K MP7 as a replacement for the IMI Uzi in .45 ACP. They are currently also being used by Task Force 7 and the Navy.