Final answer:
Irish nationalism played a significant role in changing the government of Ireland and causing it to break away from England. The Easter Rising and the establishment of the Irish Republic were notable events driven by Irish nationalists. The formation of the Irish Free State through the Anglo-Irish Treaty marked a significant step towards independence, but it did not fully satisfy all Irish republicans.
Step-by-step explanation:
The effect of Irish nationalism in changing the government of Ireland and causing it to break away from England was significant. Irish nationalists, driven by their cause, organized uprisings and revolted against British rule. One of the most notable events was the Easter Rising in 1916, where Irish revolutionaries established the Irish Republic but were ultimately suppressed by the British. The Irish Free State was later formed through the Anglo-Irish Treaty, but it did not fully satisfy all Irish republicans who wanted complete independence.