Complex sentence: The league was originally formed following the expansion of the Wessex League in 2004, as not all the clubs that disbanded from the original Hampshire League were able to meet Wessex League ground criteria and so formed a new competition.
Split into simpler sentences: The league was originally formed following the expansion of the Wessex League in 2004. As not all the clubs that disbanded from the original Hampshire League were able to meet Wessex League ground criteria and so formed a new competition.