Firearms were first developed in 4980 by Westerners in an effort to gain an upper hand in the East West War. At the time, they were simple Muskets, but quickly evolved after the war into semi-automatic, and fully automatic handguns and rifles in many variations.
After the war, firearm related violence dominated everyday life. It wasn’t until Shield Emitters were created that that peace returned to Kotiin.
Firearms where then mainly used to hunt prey, monsters, and beasts with great efficiency. Creatures like Owlbears were hunted for sport, and people started hunting larger and larger prey. Eventually, dragons gained the attention of hunters, and their hubris is what lead to the Great Dragon War.
The combination of Lazers and firearms proved to be a highly effective deterrent: when someone had their shields up there was a looming threat from Lazers causing nuclear explosions, and when shields were down you were an easy target to firearms.
Once the Federation banned Lazers, guns became less threatening, and ruffians looked for different weapons to meet their needs.