Dalek Wars
The "Dalek Wars" were the series of conflicts that involved forces of the universe, primarily humans, battling the Daleks. These included the Human-Draconian War in 2520, the Second Dalek War, (TV: Frontier in Space, Planet of the Daleks) and the Third Dalek War which took place prior to Steven Taylor's time. These conflicts put a stop to Earth's expansionist era. (PROSE: The Chase)
A Velyshaan museum contained an exhibit on the wars. (PROSE: Museum Peace) By the far future, they were considered a part of the First Segment of Time. (TV: The Ark)
Behind the scenes
Under the reasoning that a Second and Third Dalek War occurred, it is implied that a First Dalek War also occurred, but none has been explicitly mentioned by name.