James Charles McGuigan was born in Hunter River, Prince Edward Island, on 16 November 1894, the son of George and Anna (Monaghan) McGuigan. He attended the local school and Prince of Wales before entering St. Dunstan's College in Charlottetown, graduating in 1914 with an Honours BA. After obtaining his degree in Theology from the Grand Seminaire de Quebec he was ordained as a priest at St. Augustine's Church in Rustico on 26 May 1918 and taught for a year at St. Dunstan's. He would later complete post-graduate studies at the Catholic University of America.

In 1920 Rev. McGuigan accompanied Bishop Henry James O'Leary to Edmonton as his secretary. In Edmonton he became Chancellor of the Diocese from 1923-1925 Rector of St. Joseph's Cathedral, 1925-1927 and Rector of St. Joseph's Seminary, 1927-1929. On January 20, 1930 he was elected Archbishop of Regina and in 1934 he was transferred to the Archdiocese of Toronto where he served until his retirement in 1971. In 1948 he was chosen by Pope Pius XII as a member of the Papal College of Cardinals.

Cardinal McGuigan died in Toronto on 8 April 1974. On 27 August 1950, the chapel of St. Mary's of the People in his native Hunter River was dedicated to his memory.