James O'Halloran (c.1820 – June 1, 1913) was a Quebec lawyer and political figure. He was born about 1820 (some sources say 1821) near Fermoy, County Cork, Ireland and came to Canada with his family in 1828. He studied at the University of Vermont and served in the U.S. Army during the war with Mexico. He returned to Lower Canada in 1849, was admitted to the bar in 1852 and set up practice in Cowansville. He was elected to the Legislative Assembly of the Province of Canada for Missisquoi as a member of the parti rouge; he was reelected in 1863. He opposed Confederation. O'Halloran was named Queen's Counsel on February 12, 1864.
He helped establish the South Eastern Railway and served as its first president; it was later bought by the Canadian Pacific Railway. O'Halloran then became the lawyer for the Canadian Pacific Railway in Quebec. He served as first mayor of Cowansville in 1876, from 1882 to 1883 and from 1886 to 1891. He died on June 1, 1913 and was buried in the (formerly Methodist) United Church cemetery two days later.
James O'Halloran (12 January 1872 – 28 April 1943) was an Australian cricketer. He played three first-class cricket matches for Victoria in 1897.
O'Halloran (also O'Halleron, Halloran, Haloran, and in Irish, Ó hAllmhuráin or Ó hAlluráin) is the surname of a Gaelic-Irish family. The name roughly translates as 'from beyond the sea.' The family motto is 'Clann Fearghaile Abú.' This comes from the Galway branch, clann Fhergail (the family of the men of the foreigner), whose territory was extensive around Lough Corrib.
The name originates from County Clare and County Galway, with the Clare branch having links with the Dál gCais clan.