The current Constitution of Ireland is enacted by a national plebiscite of voters on July 1, 1937 in what is then the Irish Free State. The Constitution comes into effect on December 29, 1937. The Constitution is closely associated with Éamon de Valera, the President of the Executive Council of the Irish Free State at the time, who is personally eager to replace the Constitution of the Irish Free State.

There are two main motivations for replacing the constitution in 1937. Firstly, the Irish Free State constitution of 1922 is, in the eyes of many, associated with the controversial Anglo-Irish Treaty. The second motive for replacing the original constitution is primarily symbolic. De Valera wants to put an Irish stamp on the institutions of government, and chooses to do this in particular through the use of Irish nomenclature.

De Valera, as President of the Executive Council, personally supervises the writing of the Constitution. It is drafted initially by John Hearne, legal adviser to the Department of External Affairs. De Valera serves as his own External Affairs Minister, hence the use of the Department’s Legal Advisor, with whom he has previously worked closely, as opposed to the Attorney General or someone from the Department of the President of the Executive Council. He also receives significant input from John Charles McQuaid, the Catholic Archbishop of Dublin, on religious, educational, family, and social welfare issues. The text is translated into Irish over a number of drafts by a group headed by Micheál Ó Gríobhtha who works in the Department of Education.

The framers of the 1937 Constitution decide that it will be enacted not by an elected body but by the people themselves by means of a plebiscite. The preamble to the 1937 Constitution is thus written in the name not of the legislature but of “We, the people of Éire.” On June 2, 1937, the Oireachtas passes the Plebiscite (Draft Constitution) Act 1937, which mandates the holding of a plebiscite on the draft constitution on the same date as the next general election. The Dáil is dissolved on June 14, 1937, as soon as it has approved the draft constitution. The ensuing general election is held on July 1, 1937, and the plebiscite is held in parallel. The question put to voters is simply “Do you approve of the Draft Constitution which is the subject of this plebiscite?” It is passed by a plurality – 56% of voters are in favour, comprising 38.6% of the entire electorate.

Neither the Dáil resolution approving the draft Constitution nor the Plebiscite (Draft Constitution) Act 1937 provide for the plebiscite establish how the Constitution would come into force. It is the Constitution itself which states that this will occur 180 days after its approval, and that the 1922 Constitution will simultaneously be repealed. This happens on December 29, 1937, one hundred eighty days after the July 1 plebiscite.

Consequential acts are passed between July and December to provide for the establishment of, and holding elections for, the new Seanad and the Presidency, as well as for other adaptations. The Presidential Establishment Act, 1938 is passed after the Constitution has come into effect but before the first President, Douglas Hyde, takes office.