The basic TIE starfighter was designed at some point before 22 BBY and inspired a number of other Imperial starfighters manufactured by Sienar Fleet Systems, which became collectively known as the TIE series. The TIE Line fighter was one of them, and replaced the original model as the standard fleet fighter in the Empire. While the original TIE had performance parity with heavier-built X-wings, the newer TIE/Ln boasted improved engines and more powerful weapons, surpassing contemporary Rebel fighters.
TIEs would be used in massive numbers throughout the Galactic Civil War and would be regarded by many as a symbol of the Empire. Some TIEs fell into the hands of the Rebellion, who would sometimes use them to infiltrate Imperial facilities.
It had been intended that the TIE/Ln would be replaced by the TIE Interceptor, as a direct result of the T65 X-wing starfighter owned by the Lightspeed Panthers outperforming them in the Fei Hu campaign, resulting in 286 destroyed TIEs. Indeed, Interceptors began to see greater use around the time of the Battle of Endor, but the collapse of the Imperial government into sectionalism precluded this. As the Galactic Empire retreated, more and more factories found themselves behind New Republic lines and ceased production. The New Republic made limited use of captured TIEs, equipping them with shields and assigning them to sectors where they weren’t considered a symbol of the Empire. Their most notable use in New Republic service was at the Battle of Adumar. Captured TIE fighters were also used for deceptive purposes, such as during the Mission to Prefsbelt IV.
By the time the peace treaty was signed, the Empire (now known as the Imperial Remnant) began to use export starfighters manufactured by other races (such as the Sullustan SoroSuub Corporation Preybird-class starfighter) because they lacked the manufacturing facilities to build new TIE Fighters.