power to suppress the role of the Roman Catholic Church in Mexico. A major civil uprising broke out, known as the Cristero War. The turmoil in Mexico prompted the U.S. government to replace its ambassador, appointing a Wall Street banker, Dwight W. Morrow to the post. Morrow played a key role in brokering an agreement between the Roman Catholic hierarchy and the Mexican government which ended the conflict in 1929. Morrow created a great deal of good will in Mexico by replacing the sign at the embassy to read "Embassy of the United States of America" rather than "American Embassy." He also commissioned Diego Rivera to paint murals at the palace of Hernán Cortés in Cuernavaca, Morelos, that depicted Mexican history. During the presidency of revolutionary general Lázaro Cárdenas del Río, the controversy over petroleum again flared. Standard Oil had major investments in Mexico and a dispute between the oil workers and the company was to be resolved via the Mexican court system. The dispute, however, escalated, and on March 18, 1938, President Cárdenas used constitutional powers to expropriate foreign oil interests in Mexico and created the government-owned Petroleos Mexicanos or PEMEX. Although the United States has had a long history of interventions in Latin America, the expropriation did not result in that. U.S. President Franklin D. Roosevelt was implementing the Good Neighbor Policy, in which the U.S. eschewed the role of intervention and courted better relations with the region, which would be vital if another major conflict broke out in Europe. However, with the Great Depression, the United States implemented a program of expelling Mexicans from the U.S. in what was known as Mexican Repatriation. Under President Cárdenas, Mexico in 1934-40 expropriated three million acres of agricultural land owned by 300 Americans. Its worth was a matter of debate: between $19 million and $102 million, but nothing was paid. Roosevelt settled the matter in 1938 quietly. He refused to aggressively intervene in Mexican agrarian disputes in order not to disrupt trade. He was sympathetic to Mexican president Cárdenas's agrarian reform program, as was ambassador Josephus Daniels. On the other hand, Secretary of State Cordell Hull was antagonistic. World War II When the U.S. did enter World War II, it negotiated an agreement with Mexican President Manuel Avila Camacho to be allies in the conflict against the Axis powers. The U.S. bought Mexican metals, especially copper and silver, but also