The Firebirds were a 1990 expansion team, the Rockers were a 1992 expansion team, The ThunderBolts relocated from Columbus, Ohio following the 1991 season (their first in the league), and the Drive were a 1988 expansion team.
In the early years of the league, the Firebirds joined as an expansion team in 1990, followed by the Rockers in 1992. The ThunderBolts relocated from Columbus, Ohio after their first season in 1991, while the Drive debuted as an expansion team in 1988.