One of five children born to Archibald McNeill, a Roman Catholic working class “baker, sailor and merchant,” and his wife, Rosetta (née McAuley) McNeill, McNeill is the brother of nationalist leader Eoin MacNeill. He serves as a high-ranking member of the Indian Civil Service in Calcutta.
Although unconnected with the Easter Rising in 1916, McNeill is arrested and jailed by the British Dublin Castle administration. On release, he is elected to Dublin County Council, becoming its chairman. He serves as a member of the committee under Michael Collins, the chairman of the Provisional Government, that drafts the Constitution of the Irish Free State. He is subsequently appointed as High Commissioner from Ireland to the United Kingdom.
When the first Governor-General of the Irish Free State, Tim Healy, retires in December 1927, McNeill is proposed as his replacement by the Irish government of W. T. Cosgrave and duly appointed by King George V as Governor-General of the Irish Free State.
In office, McNeill clashes with the King’s Private Secretary when he insists on following the constitutional advice of his Irish ministers, rather than that of the Palace, in procedures relating to the receipt of Letters of Credence accrediting ambassadors to the King in Ireland. He also refuses to attend ceremonies in Trinity College, Dublin, when some elements in the college try to ensure that the old British national anthem God Save the King is played, rather than the new Irish anthem, Amhrán na bhFiann.
When Éamon de Valera is nominated as President of the Executive Council of the Irish Free State in 1932, McNeill opts to travel to Leinster House, the parliament buildings, to appoint de Valera, rather than to require that he go to the Viceregal Lodge, the Governor-General’s residence and the former seat of British Lords Lieutenant, to avoid embarrassing de Valera, who is a republican.
However, McNeill’s tact is not reciprocated by de Valera’s government, and some of its ministers seek to humiliate him as the King’s representative by withdrawing the Irish Army‘s band from playing at functions he attends and demanding he withdraw invitations to visitors to meet him. In one notorious incident in April, two ministers, Seán T. O’Kelly (a future President of Ireland) and Frank Aiken, publicly walk out of a diplomatic function when McNeill, there as the guest of the French ambassador, arrives. In a fury, McNeill writes to de Valera demanding an apology for this treatment. When none is forthcoming, apart from an ambiguous message from de Valera that could be interpreted as partially blaming McNeill for attending functions at which ministers would be present, he publishes his correspondence with de Valera, even though de Valera had formally advised him not to do so. De Valera then demands that George V dismiss him.
The King engineers a compromise, whereby de Valera withdraws his dismissal request and McNeill, who is due to retire at the end of 1932, will push forward his retirement date by a month or so. McNeill, at the King’s request, resigns on November 1, 1932.
In June 1932 John Charles McQuaid, President of Blackrock College hosts an extravagant garden party to welcome Papal Legate Lorenzo Lauri, who had arrived in Ireland to represent Pope Pius XI at the 31st International Eucharistic Congress. While de Valera maintains a very high profile at the event, McQuaid, at de Valera’s request, goes to great lengths to avoid MacNeill to the extent possible.
McNeill dies on December 12, 1938 at the age of 69 in London. His widow Josephine is appointed Minister to the Hague by Seán MacBride, Minister for External Affairs in the coalition government of 1948.