O'Connor, Arthur James Kickham (‘Art’) (1888–1950), politician and judge, was born 18 May 1888 at Elm Hall, Loughlinstown, Celbridge, Co. Kildare, second son among four sons and five daughters of Art O'Connor, farmer, and Elizabeth O'Connor (neé Saul). He was educated at Holy Faith School, Celbridge, and Blackrock College, Dublin (1899–1907), before attending TCD. He graduated with an engineering degree (1911) and was immediately employed by Kildare county council.
O'Connor, an enthusiastic supporter of the GAA and an active member of the Gaelic League, joined Sinn Féin. He was arrested in connection with the so-called ‘German plot’ (May 1918) and imprisoned in Durham. During his internment he was selected to contest the 1918 general election for Sinn Féin in the constituency of Kildare South. He was elected, easily defeating the nationalist candidate, Denis McBride. O'Connor was appointed substitute director of agriculture in the first dáil, following the arrest of Robert Barton (qv) in January 1920. O'Connor dealt personally with all correspondence of a strictly agricultural nature, being surreptitiously assisted in this task by Daniel Twomey (qv). His staff at the department's headquarters at 5 North Earl St. included León Ó Broin (qv). After a good deal of deliberation O'Connor's department did not take a confrontational attitude toward the existing Department of Agriculture and Technical Instruction (DATI). He dithered, but ultimately recommended that rather than boycotting the DATI, republicans should attempt to take control of the democratic elements of that department's apparatus. The republican department's main concern during O'Connor's tenure was land distribution. Agrarian violence reached a peak in the spring of 1920. O'Connor was unsympathetic towards the agitators. He toured the most troubled areas, Kerry, and then Galway and Mayo, with Kevin O'Shiel (qv) at the suggestion of Conor Maguire (qv). They began to conduct land tribunals on an ad hoc basis (initially in Ballinasloe in May 1920). In September O'Connor convinced the dáil to create the dáil land commission with O'Sheil and Maguire as commissioners.
In February 1921 O'Connor was nominated to the dáil's labour commission and was returned unopposed for the constituency of Kildare–Wicklow in May. He was appointed minister for agriculture (outside cabinet) in the second dáil. His ministerial career ended when he opposed the treaty and failed to get reelected in 1922. O'Connor fought in the civil war, witnessing the suicidal charge of Cathal Brugha (qv) from the Granville Hotel, O'Connell St. (5 July 1922). Although interned in Mountjoy and Kilmainham, O'Connor was unlucky not to win a seat in Kildare (1923). He published Notes on national economy (1925) in which he advocated the Sinn Féin policies of increased tillage and autarky. In February 1926 he received 15,400 votes, but was narrowly defeated at a by-election in Leix–Offaly. A month later he became president of the republic when Eamon de Valera (qv) resigned. This lofty position did not prevent his heavy defeat in the general election of June 1927. He never ran for office again. Generally regarded as a nice man but an ineffective figurehead, O'Connor engendered bitterness when he resigned the presidency in 1927. His departure became necessary when, on receiving a TCD law degree, he was called to the bar; this involved recognising Saorstát Éireann.
O'Connor built up a strong practice on the eastern circuit and was called to the inner bar (1944). He became standing counsel to the revenue commissioners (1944–7) and circuit court judge for Cork city and county (1947–50), resigning when he was appointed chairman of the military services pensions tribunal. He was in this position for a matter of months when he died at Elm Hall, 10 May 1950. He lived in Celbridge for most of his life and was very involved in Celbridge Development Association. O'Connor, who never married, left £4,003 to his sister, Frances.