Complex sentence: Informally established in the early 1970s the constitutions and organisations of each of the nine boards varied, Northern Arts Board was created by a coalition of Local Government while others were voluntary organisations created by artists.
Split into simpler sentences: Informally established in the early 1970s, the constitutions and organisations of each of the nine boards varied. The Northern Arts Board was created by a coalition of Local Government while others were voluntary organisations created by artists.