The house flag of Imperial Oil Ltd, Toronto. A rectangular flag divided diagonally in blue and white, with the letters 'I. O. LTD.' in white and blue. The flag is made of a wool and synthetic fibre bunting. It has a cotton hoist and is machine sewn. A rope and two Inglefield clips is attached.

Imperial Oil was founded in London, Ontario, Canada in 1880. Imperial operated refineries in Southwestern Ontario and spent many years trying to find other sources of oil in Canada. The Standard Oil Company of New Jersey, founded by John D. Rockefeller, obtained a majority interest in Imperial Oil in 1898 which continues to this day under the ExxonMobil Corporation. The turn of the century and subsequent growth of the auto industry introduced Imperial as a source of petrol as well as other petroleum products. In 1914, the International Petroleum Company was created as a subsidiary of Imperial in order to tap into the crude oil market in South America. The ‘Imperial’ was the company’s first oil tanker, and transported crude oil from Ohio to Imperial’s refinery in Sarnia, Ontario. Imperial operated its own shipping fleet until 1935, when the Imperial Oil Shipping Company was created (considered a separate company from Imperial Oil) to reduce tax implications under Canadian laws. Following decades of futile attempts to find additional sources of oil in Canada, Imperial finally had a stroke of good luck in Leduc, Alberta in 1947. Leduc was only the beginning; Imperial, as well as other companies, discovered that a large area around Leduc was just as productive, which created quite a boom in Alberta. In 1950, the Interprovincial Pipeline was constructed, which stretched from Edmonton to Superior, Wisconsin. Transport was further aided by Imperial’s Great Lakes tankers such as the ‘Imperial Leduc’, which would make about 50 trips during the April-December season, carrying crude oil from Alberta to a refinery on Lake Huron. Further technological advances continued in the next few decades, including the company’s ventures into oil sands projects. Imperial also began using the trade name Esso for its products, due to its majority ownership by the company. Currently, Imperial Oil operates four major refineries in Canada, as well as numerous research facilities, oil sands operations, and Esso brand service stations. It currently produces about six percent of Canada’s total energy supply through petroleum products and natural gas.