Revolution and partition
The First Dáil met on 21 January 1919 and declared independence. The War of Independence followed. The Government of Ireland Act 1920 created separate institutions for Northern Ireland and Southern Ireland, establishing partition.
Key stages in the State’s development
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| Date | Event | Why it matters |
|---|---|---|
| 1919 | First Dáil declares independence | An asserted republic during the War of Independence |
| 1921 | Anglo-Irish Treaty signed | A settlement providing for a self-governing Free State |
| 1922 | Free State established | A 26-county state began under its own constitution |
| 1937 | New Constitution comes into operation | Established the offices of Taoiseach and President |
| 1949 | Republic of Ireland Act comes into operation | Ended the Crown’s remaining statutory role in external relations |
Treaty and Civil War
The Anglo-Irish Treaty was signed on 6 December 1921 and approved by the Dáil in January 1922. It provided for a self-governing Irish Free State within the British Commonwealth, with an oath involving allegiance to the Crown. Northern Ireland could opt out and did so. Disagreement over the Treaty contributed to the Civil War of 1922–23.
From Free State to today
The Free State came into being on 6 December 1922, governing 26 counties. Its 1922 constitution established a parliament and government. The 1937 Constitution replaced it and created the offices of Taoiseach and President. The Republic of Ireland Act 1948 came into operation in 1949, ending the remaining statutory role of the British Crown in external relations.
Why the Treaty was contested
The Treaty offered substantial self-government but did not establish the independent republic sought by its opponents. The oath and the continuing connection with the Crown became points of conflict. Supporters regarded the settlement as a means to build greater freedom. These disagreements divided families and political allies, not just institutions.
From declaration to state
The 1919 declaration and the 1922 Free State are distinct milestones. The First Dáil asserted an Irish republic during a revolutionary period. The Treaty settlement created a recognised self-governing state with a different constitutional status. The six counties of Northern Ireland did not become part of the state that remained after the opt-out. Recognising the difference helps explain why the Treaty could be welcomed as a major advance and rejected as a compromise by others.
A changing constitution
Statehood was a process as well as an event. The 1922 and 1937 constitutions created different institutions and the relationship with Britain changed through legislation and political decisions. The dates 1919, 1922, 1937 and 1949 therefore answer different questions: declaration, the Free State’s establishment, a new constitutional order and the operation of the Republic of Ireland Act.
The Treaty vote and its consequences
The Dáil approved the Treaty by 64 votes to 57 on 7 January 1922. The narrow division reflected a real disagreement about the settlement, not a choice between independence and no change. A provisional government was established to carry the agreement forward, while the split in the independence movement deepened. Fighting began in June 1922, before the Free State formally came into being that December. The Civil War continued into 1923. Understanding this sequence helps explain why state institutions were built during conflict and why the Treaty remained politically consequential long after it was signed.