1. Northern Ireland continued to compete as 'Ireland' until season 1976-77 when they officially changed their name.
2. The Championships were suspended from 1914-15 to 1918-19 due to World War One and were further suspended from 1939-40 to 1944-45 due to World War Two.
3. The 1980-81 Championship was cancelled due to civil unrest in Northern Ireland.
4. The Four Associations' Tournament, between Scotland, Wales, Northern Ireland and the Republic of Ireland, was launched in 2011.