James Vincent O'Loghlin (25 November 1852 – 4 December 1925) was an Australian politician. Born in Gumeracha, South Australia, he was educated at the Classical and Commercial Academy in Adelaide before becoming a farmer and wheat buyer. Later a journalist and owner of country newspapers, he was active in Irish nationalist organisations. In 1888, he was elected to the South Australian Legislative Council for the Labor Party, serving until 1902. In 1907, he was appointed to the Australian Senate after the election of Anti-Socialist Senator Joseph Vardon was declared void. However, O'Loghlin's own appointment was declared void, and he and Vardon contested a special election, which was won by Vardon. He was elected in his own right as a Labor Senator in 1913, but was defeated in 1919, having been the only one of South Australia's five Labor senators not to defect to the Nationalist Party after the 1916 split over conscription. O'Loghlin returned to the Senate in 1922, but died in 1925; the South Australian Nationalist Government successfully installed Nationalist Henry Barwell in his vacancy.[1]