John Joseph Caldwell Abbott was born on March 12, 1821, in St. Andrews, in the county of Argenteuil, Lower Canada (now Quebec). He was the eldest son of the Rev. Joseph Abbott and Harriet Bradford Abbott. He received his early education in St. Andrews and in Montreal, then entered McGill University. He took his law degree in 1847. In 1849 he married Mary Bethune. They had six children.

Abbott was named queen's counsel in 1862. He served as counsel for the Canadian Pacific Railway from 1880 to 1887, when he became a director. For several years he was dean of the Faculty of Law at McGill University. He held the office of mayor of Montreal from 1887 to 1889.

One of Abbott's first political acts was to sign, in 1849, an annexation manifesto which favored the union of Canada with the United States. The union movement, brought on by a business depression, lasted only a short time. In 1859 Abbott was elected to the Legislative Assembly of Canada.

As legal adviser to Hugh Allan, one of the builders of the Canadian Pacific Railway, Abbott was implicated in the Pacific Scandal of 1873. One of his confidential clerks furnished the evidence that brought about the fall of the Macdonald government in that year and the defeat of Abbott in the elections of 1874. In 1881 Abbott was returned to the House of Commons, and in 1887 he was appointed to the Dominion Senate. Upon the death of Macdonald in 1891, Abbott was a compromise choice for prime minister.

Abbott was 70 years of age and in declining health when he became prime minister. During his short term of office he accomplished a major revision of the jury law. He drafted an act which is the basis of Canadian law on insolvency today.

On Dec. 5, 1892, Abbott resigned as prime minister because of ill health. That same year he was made a knight commander of the Order of St. Michael and St. George. He died in Montreal on Oct. 30, 1893.