The Constitution (Removal of Oath) Act 1933 (act no. 6 of 1933, previously bill no. 2 of 1932)was an Act of the Oireachtas of the Irish Free State amending the Constitution of the Irish Free State and the Constitution of the Irish Free State (Saorstát Eireann) Act 1922. It removed the Oath of Allegiance required of members of the Oireachtas (legislature) and of non-Oireachtas extern ministers.
The oath, pledging allegiance to the Constitution and fidelity to George V as King of Ireland, was required by the Anglo-Irish Treaty signed in 1921, and had been the symbolic focus of Irish republican opposition to the Treaty in the 1922–23 Irish Civil War. When Fianna Fáil was founded in 1926 by veterans of the losing anti-Treaty side in the Civil War, abolishing the oath was a core aim. It was a main item in the manifesto for its successful 1932 general election campaign, after which it formed a minority government whose first action was to introduce the Constitution (Removal of Oath) Bill 1932. Seanad Éireann had more ex-unionists and others conciliatory towards the United Kingdom, and voted to reject the bill unless the Treaty could be amended by agreement. After the 1933 general election, the Fianna Fáil majority government was able to override the Seanad and enact the law.