1.Irish separatists want full independence,similar to that of United States,while Britain want Ireland to be like Canada,with British monarch still as the head of state.
2.Six northeastern counties,mainly protestants,choose to remain with Britain as Northern Ireland.
3.Split among Irish nationalists over the Anglo-Irish treaty.
4.Armed conflicts between different factions of the nationalists prior to Civil war.
5.The June Election of 1922,and the subsequent repression on anti-treaty nationalist.
Are those enough?
Can I have more points?