Short answers, pulled from the story.
Douglas Niles and Steve Winter designed the original Battlesystem boxed set that arrived on store shelves in 1985. They created the game to serve as a successor to the medieval miniature wargame Chainmail.
The first edition contained four battle scenarios including three linked campaigns for generic fantasy settings and one advanced scenario titled Battle of Qualinost. The fourth scenario took place during the same time period as DL2 Dragons of Flame while heroes remained in Pax Tharkas.
The second edition appeared in 1989 and increased base sizes to accommodate standard practice 25 mm miniatures instead of requiring 15 mm figures. All photographs in the rulebook featured 25 mm miniatures staged in elaborate battlefield dioramas.
The original Battlesystem set won the H.G. Wells Award shortly after its release in 1985. The second edition claimed the 1989 Origins Award for Best Miniatures Rules of 1989.
Sales figures never reached levels that justified continued active development or expansion for the system. This lack of commercial success led to the game not being actively supported in role playing systems like Dark Sun.