Rugby Union of Ireland

The RUoI was created after World War II when many of the Irish Provincial Rugby clubs folded. Of the twenty-four clubs from the IPR only fourteen remained. Six of those participated in the 1947 and 1948 seasons before all fourteen joined in 1949. The game became professional in 1989 and ten clubs left the RUoI to join Pro Rugby Ireland. The remaining twelve clubs created Irish Amateur Rugby.