Complex sentence: On 8 September 1997, the football clubs in the Premier Division decided to split from the Scottish Football League and form the Scottish Premier League, following an earlier example in England, which came into force during the 1992--93 season.
Split into simpler sentences: On 8 September 1997, the clubs in the Premier Division decided to split from the Scottish Football League and form a Scottish Premier League. This followed an earlier example in England, which came into force during the 1992--93 season.