Sometimes simply known as D'Arcy McGee, he was born on April 13, 1825 in Carlingford, Ireland. In 1843 at age 17 he emigrated to the United States where he found work as assistant editor of Patrick Donahoe's Boston Pilot Catholic newspaper in Boston, Massachusetts. A few years later he returned to Ireland where he became politically active and edited the nationalist newspaper Nation. His support for the Fenians, forerunners of Sinn Féin, and his involvement in the armed uprising in Tipperary in 1848 resulted in a warrant for his arrest. McGee escaped the country and returned to the United States.
In the States, he founded Irish-American publications in New York City and Boston, and generally supported the cause of Irish immigrants. In 1857 he went to Canada where he set up the publication of the New Era in Montreal, Quebec. Politically active, his anti-England sentiments showed up again in his advocacy of Canadian independence from Great Britain. In 1858 he was elected to the Parliament of Canada and worked for the creation of an independent Canada.
Moderating his radical Irish views, McGee denounced the Fenian Brotherhood in America that advocated a forcible takeover of Canada from Great Britain by the United States. A faction of American Fenians sent an invasion force into Canada in 1866 that was repelled and arrested by American authorities. Canadians, with Irish sympathizers in their midst, and spurred by numerous rumors of another, more massive invasion, lived in fear of the Fenians for several years.
On April 7, 1868, D'Arcy McGee was assassinated in Ottawa, Ontario. Patrick J. Whelan, a Fenian sympathizer who was accused, tried, convicted, and hanged for the crime. Decades later, his guilt was questioned and many believe that he was falsely accused in order to be a scapegoat for the murder. His case is dramatized in the Canadian play, Blood On The Moon.