McMaster, William (1811–87), merchant, Canadian senator, and philanthropist, was born 24 December 1811 in Co. Tyrone, the son of William McMaster, linen merchant. Privately educated by local teachers, he began work in a mercantile house before moving to New York and then York (Toronto), in August 1833. He quickly became a successful clerk in a wholesale and retail dry goods firm, and within two years had been made a partner. His fortune continued, and in 1844 he took over the entire business. Having no sons, in 1859 he brought over two nephews from Ireland to become partners, and by 1860 was one of the wealthiest merchants in Toronto.
Active in the commercial expansion of Toronto, McMaster sought to augment its wholesale distribution network in Canada West (Ontario) at the expense of the more dominant centre of Montreal in Canada East (Quebec). From the 1850s he was nominated director of several of the largest banking, insurance, and railway companies in the Canadas. As a director of the Bank of Montreal in 1864, he was annoyed by the bank's restriction of credit to businessmen in Canada West; consequently he left the bank and was instrumental in the formation of the Canadian Bank of Commerce, serving as its first president (1867–86). He was also director of the Ontario Bank, the Wellington, Grey and Bruce Railway, the Great Western Railway (1867–74), the Toronto General Trusts Company, and the London and Canadian Loan and Agency Company, vice-president of Confederation Life Association (1871–87), and president of the Freehold Loan and Savings Company.
As McMaster spent less time in his wholesale business and more time directing financial institutions, he also entered politics and government, being elected as a Liberal for the Midland division of the Legislative Council of the United Provinces of Canada (1862–7), an elective body responsible for examination of legislation passed by the legislative assembly. He sympathised with reformers concerned with the commercial expansion of Canada West and sought to improve the position of evangelical nonconformists – McMaster himself was a baptist. With the creation of the dominion of Canada in 1867, he was appointed in October of that year a member of the senate, the non-elected upper house in parliament, a post he retained until his death.
McMaster is best known for his philanthropic work, in particular his support of education and the baptist church. After the closure of the baptist college in Montreal in 1849, he funded its successor, the Canadian Literary Institute, opened in Woodstock, Canada West, in 1860 and renamed Woodstock College in 1883, offering instruction in arts and theology. In the late 1870s the theological department moved to Toronto, where it was named the Toronto Baptist College, and in 1879 McMaster provided a site for it, with a substantial initial outlay of $100,000 and an annual contribution of $14,000. In the mid-1880s there were plans to federate the college with the University of Toronto, but because of McMaster's insistence on an independent baptist college the plans were scrapped, and by a provincial act in March 1887 Woodstock College and the Toronto Baptist College were united under the name of McMaster University. In his will McMaster left the bulk of his estate, $900,000, as endowment for the new university, which moved to Hamilton, Ontario, in 1930. He also gave a substantial donation of $60,000 for the construction of a large baptist church in the early 1870s.
McMaster was married twice: in 1851 to Mary Henderson (d. 1868) and in 1871 to Susan Fraser, née Moulton, the widow of a successful American businessman. There were no children from either marriage. McMaster died in Toronto in September 1887, after which his widow donated their Bloor Street mansion to McMaster University; it became Moulton College, a school for women.