S&w
Developed in the late 1800's
.22 Long was developed @ 1871, Uses the same case as the 22LR but with a 29 g bullet. ,22 Long Rifle developed by Peters Cartridge in 1887. Uses bullets in the 32-40 g range
The .22 LR cartridge was developed in 1886. It used the case of the .22 Long, but an improved bullet.
The 22 LR wasn't developed until the 1880's.
Th XM8 rifle was developed by the US Army from the late 1990s to the early 2000s. It is a lightweight assault rifle. The US Army collaborated with Heckler & Koch to design the XM8 rifle.
The Kentucky Long-Rifle is known alternatively as the Pennsylvania Long-Rifle, and the American Long-Rifle. Being from the Commonwealth of Kentucly the author of this answer asserts that Kentucky Long-Rifle is the one and true proper name. Now, as to the meat of the question. This long pattern of rifle first appeared in Pennsylvania as a product of German immigrants to the American Colonies. Due to its capabilities the gun rapidly proliferated from there. This type of firearm came to be known as the 'Kentucky Long-Rifle' in later years for a number of reasons. The most important of which would be that in colonial times the men of Kentucky had a reputation not only as hunters; but as Sharpshooters wielding this distinctive family of long-rifles.
Among the first, the Greener rifle was made in the 1860s.
The gun was developed in 1947. It was adopted by the Soviet Union in 1949.
The Imperial Russian Army developed the Mosin Nagant Rifle between 1882 and 1891. In 1891 Russia officially adopted the Mosin Nagant Rifle. The rifle was designed by Sergei Mosin from Russia and Leon Nagant from Belgium. This is where the name of the rifle comes from.
Originally, there were shorts, longs and extra longs. The Long Rifle cartridge was developed in 1887 by Stevens, when they combined the case of the Long cartridge with the bullet of the Extra Long. The Extra Long has been obsolete for many years, and the .22 Long is rarely seen any more.
The F2000 assault rifle was developed in Belgium by Fabrique Nationale d'Herstal.
The 44 rim fire Henry rifle was developed by Benjamin Tyler Henry.