In 1953, British Petroleum Company (BP) entered the Canadian market through the purchase of a minority stake in Calgary-based Triad Oil Company. In the early 1950s, the power struggle between oil companies and host governments in Middle East started, which hampered operations of British Petroleum in the region, and prompted it to diversify its operations beyond the heavily Middle East dependent oil production. The Canadian holding company of British Petroleum was renamed BP Canada in 1969; and in 1971, it acquired 97.8% stake of Supertest.