He was born at Mount Auburn, Richmond, Dublin, the son of James Deakin, a traveller, and Mary Anne Tate.
[2] Ten years later, the couple was living at 37 Thomond Terrace, Inn's Quay, Dublin, with their three children.
[4] Deakin became involved in the Irish nationalist movement during the early 1900s, along with other Protestant nationalists such as George Irvine, Ernest Blythe and Seán O'Casey, and within a short time became a high-ranking member in the Drumcondra branch of the Irish Republican Brotherhood.
In 1913, he succeeded John Mulholland as president of the IRB before acceding to Denis McCullough the following year.
[4] He died of a coronary thrombosis on 10 December 1952 in Drumcollogher, County Limerick – where he had moved from Dublin about a decade previously – and was buried in the local cemetery.