Imperial Oil Limited (French: Compagnie Pétrolière Impériale Ltée) is a Canadian petroleum company.

[19] Imperial Oil's charter noted that its goal was to "find, produce, refine and distribute petroleum and its products throughout Canada.

[20] In 1883, the Victor works was struck by lightning and burned to the ground, and under Englehart's direction, the company concentrated its refining efforts at Petrolia.

[22] Frasch had taken the position primarily to supervise the installation of his refining method at the Silver Star refinery and resigned in February 1885 once the work was complete.

[22] The pair purchased an idle refinery in London, and Frasch began experimenting on a way to remove the sulphur content in the oil pumped at Lambton County.

[24] Between 1885 and 1887, Frasch discovered that mixing copper oxide with the oil during the distilling process would remove the sulphur content and odour from the refined product.

[26] After returning to the United States, Frasch perfected his desulphurization strategy, and Standard Oil held a monopoly on the process until 1905.

[33][34] Following the deal, Imperial Oil shut down the Silver Star refinery in Petrolia and moved its refining operations to Sarnia, Ontario.

[33] In a landmark 1911 anti-trust case, the U.S. Supreme Court ordered Standard Oil to break up into 34 separate companies.

[41] Frederick A. Fitzgerald, 1880–1889 Frank Q. Barstow, 1889–1908 Horace Chamberlain, 1908–1911 Walter C. Teagle, 1914–1918 William J. Hanna, 1918–1919 Charles O. Stillman, 1919–1933 G. Harrison Smith, 1933–1944 Richard V. LeSueur, 1944–1945 Henry H. Hewetson, 1945–1949 George L. Stewart, 1949–1953 John R. White, 1953–1960 William O. Twaits, 1960–1970 John A. Armstrong, 1970–1979 James R. Livingstone, 1979–1982 Arden R. Haynes, 1982–1988 Robert B. Peterson, 1988–1992 Ronald A. Brenneman, 1992–1994 Robert B. Peterson, 1994–2001 Timothy J. Hearn, 2001–2007 Bruce H. March, 2007–2013 Richard M. Kruger, 2013–2019 Bradley W. Corson, 2019– Frederick A. Fitzgerald, 1889–1905 G. Harrison Smith, 1944–1945 Richard V. LeSueur, 1945 Frank W. Pierce, 1945–1947 George L. Stewart, 1947–1949 Henry H. Hewetson, 1949–1950 George L. Stewart, 1953–1955 John R. White, 1960–19??

William O. Twaits, 1970–1974 John A. Armstrong, 1974–1981 Donald K. McIvor, 1981–1985 Arden R. Haynes, 1985–1992 Robert B. Peterson, 1992–2002 Timothy J. Hearn, 2002–2008 Bruce H. March, 2008–2013 Richard M. Kruger, 2013–2019 Bradley W. Corson, 2019– Imperial Oil supplied more than 2,000 service stations as of October 2020,[42] all of which were owned by third parties.

With ExxonMobil having majority ownership, Imperial Oil licences its parent company's brands, including the Esso and Mobil names for service stations, and the Speedpass electronic payment system.

On March 13, 2018, Loblaw Companies announced that it had reached a deal for the Esso-branded stations to join the PC Optimum rewards program, beginning on June 1, 2018.