James Aubrey (Seamus) Deakin (19 June 1874 – 10 December 1952) was an Irish nationalist and member of theIrish Republican Brotherhood (IRB), of which he was president from 1913 to 1914.

He was born at Mount Auburn, Richmond, Dublin, the son of James Deakin, a traveller, and Mary Anne Tate.^[1] His family wasChurch of Ireland. In 1901, he was living at 27 Millmount Avenue,Drumcondra, with his wife, Catherine, a Scottish-born Presbyterian.^[2] Ten years later, the couple was living at 37 Thomond Terrace, Inn's Quay, Dublin, with their three children.^[3]

Deakin worked as a chemist in Hoyt's pharmacy inO'Connell Street and later owned his own shop inPhibsborough.^[4] Deakin became involved in the Irish nationalist movement during the early 1900s, along with otherProtestant nationalists such asGeorge Irvine,Ernest Blythe andSeán O'Casey, and within a short time became a high-ranking member in theDrumcondra branch of the Irish Republican Brotherhood. In 1913, he succeededJohn Mulholland as president of the IRB before acceding toDenis McCullough the following year. Deakin resigned from the Supreme Council and from the IRB about August 1914.^[5]

It is a common belief that he emigrated to the US, but that is almost certainly not true.^[4] He died of a coronary thrombosis on 10 December 1952 inDrumcollogher,County Limerick – where he had moved from Dublin about a decade previously – and was buried in the local cemetery.^[6]

• Martin, Francis X.The Irish Volunteers, 1913–1915: Recollections and Documents. Dublin: James Duffy & Co., 1963.

• 1874 births
• 1952 deaths
• Early Sinn Féin politicians
• Irish Anglicans
• Irish Republican Army (1919–1922) members
• Members of the Irish Republican Brotherhood
• Protestant Irish nationalists

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