negotiated the Anglo-Irish Treaty in London from 11 October to 6 December 1921. The Irish delegates set up headquarters at Hans Place in Knightsbridge and it was here in private discussions that the decision was taken on 5 December to recommend the Treaty to Dáil Éireann. The Second Dáil Éireann narrowly ratified the Treaty.
In accordance with the Treaty, on 6 December 1922 the entire island of Ireland became a self-governing British dominion called the Irish Free State (Saorstát Éireann). Under the Constitution of the Irish Free State, the Parliament of Northern Ireland had the option to leave the Irish Free State exactly one month later and return to the United Kingdom. During the intervening period, the powers of the Parliament of the Irish Free State and Executive Council of the Irish Free State did not extend to Northern Ireland. Northern Ireland exercised its right under the Treaty to opt out of the new dominion and rejoined the United Kingdom on 8 December 1922. It did so by making an Address to the King requesting, "that the powers of the Parliament and Government of the Irish Free State shall no longer extend to Northern Ireland." However, the Irish Free State was a constitutional monarchy over which the British monarch reigned. It had a Governor-General, a bicameral parliament, a cabinet called the "Executive Council" and a prime minister called the President of the Executive Council.
Irish Civil War
The Irish Civil War was the consequence of the creation of the Irish Free State. Anti-Treaty forces, led by Éamon de Valera, objected to the fact that acceptance of the Treaty abolished the Irish Republic of 1919 to which they had sworn loyalty, arguing in the face of public support for the settlement that the "people have no right to do wrong". They objected most to the fact that the state would remain part of the British Commonwealth and that members of the Free State Parliament would have to swear, what the Anti-Treaty
