Within a few years of arriving in Montreal, Redpath began running his own sizeable construction business. He was involved in major projects such as the construction of the
Lachine Canal and locks that proved key to future commercial development of the city of Montreal. Beginning in 1689, attempts were made by the
French Colonial government and several others to build a canal that would allow ships to bypass the treacherous
Lachine Rapids. After more than 130 years of failure, with funding from the recently formed
Bank of Montreal, the consortium, of which Redpath was a major part, was successful in its construction and the new canal officially opened in 1825. The Lachine canal substantially increased shipping, turning Montreal into one of the largest ports in North America. Because the land along the canal belonged to the
Roman Catholic Sulpician Order it remained unused for another twenty years until Redpath and other businessmen were finally able to purchase plots along the canal. As a result of the land being opened to development, on the canal's banks came the construction of large new manufacturing plants, drawn there because of the ready source of water from the canal that could be used in the production process and provide the steam power to drive machinery. It was these industries, including Redpath's construction of the first sugar refinery in Canada, that made Montreal the industrial metropolis of Canada and by the time of his death, John Redpath witnessed traffic go from 600 small vessels passing through the canal each year to more than 13,000 large ships. John Redpath's success in building the Lachine Canal led to further major projects including his partnering with
Thomas McKay, to construct the locks at
Jones Falls, Ontario, on the giant
Rideau Canal project between 1827 and 1828. In addition, Redpath built the
Notre-Dame Basilica and some of the first buildings at
McGill University. The
Redpath Sugar refinery proved to be a major Montreal employer, within a few years annually processing approximately 7,000 tons of raw sugar imported from the
West Indies aboard Redpath-owned ships. Originally called the Canada Sugar Refining Co., after his son
Peter (1821–1894) joined the business the company's name was changed to John Redpath & Son. Four years later in 1861, Redpath's son-in-law
George Alexander Drummond (1829–1910) also joined the company. In addition to his own industrial enterprises, Redpath invested in numerous businesses that greatly benefited the Montreal economy. In addition to his own cargo vessels to serve his sugar refinery, he had investments in the Montreal Towboat Company. He also helped finance the
Montreal Telegraph Company and the Montreal Fire Assurance Company, serving as a director of both companies. He also committed substantial funds to develop the economies of Quebec's
Eastern Townships, including investments in the Capel Copper operations, the Belvedere Mining and Smelting Company, Rockland Slate Company, Bear Creek Coal, and Melbourne Slate Co. As a result of his business acumen, in 1833 Redpath was invited to serve on the board of directors of the
Bank of Montreal, a position he would hold for 36 years. Canada has always had a very small population and in the developing years of the early 19th century, that small population meant there was limited financial resources for business to draw upon. Because major business development was still dependent upon funding from the
London Stock Exchange, Redpath understood the need for Canada to begin the long process of developing its own capital markets. As such, he was a promoter of the Montreal Investment Association, the forerunner of the
Montreal Stock Exchange. Coming from the Scottish working class Redpath had an inherent mistrust of the aristocratic power structure in England and did not view England as the mother country as other Canadians such as
Robert Baldwin did. Numerous complaints by business officials in the Canadian colony were ignored by the British authorities and the situation became intolerable when the government in London decided to abolish tariffs that protected
Lower Canada producers from the established and well-financed British companies. Understanding that fighting these powerful forces in Britain was costly and nearly impossible, along with other businessmen who had invested in Canada, Redpath lent his support to the
Annexation Movement in Canada in an effort to leverage the situation. This group promoted the idea of the Canadian Provinces joining the United States, an idea that had been touted on prior occasions. It had been unfair taxes and tariffs that led to the
American Revolution and while the Annexation Movement was short-lived, the growing support for such an idea, particularly from powerful men like Redpath,
John Molson,
Louis-Joseph Papineau, and
Alexander Galt, caused the British authorities to make changes that resulted in the
Canadian–American Reciprocity Treaty of 1854. ==Political career and philanthropy==