CALLES, PLUTARCO ELIAS ), Mexican statesman and military leader, president of Mexico in 1924-28, born at Guaymas, Sonora, Sept. 25, 1877. Little is known of his early life, however, it is certain that almost to manhood he lived the life of the poorer class. He attended the school of his native town, where at the age of 17 years he became a teacher in the primary school. Later he became superintendent of schools in Hermosillo, and it was there that he began to show the qualities which have made him an outstanding figure in Mexico. His interest in social and economic reforms caused him to join the revolutionary movement which overthrew Porfirio Diaz. In 1913 he joined the forces of Gen. Carranza in the struggle against the Huerta administration, attaining the rank of general. In the border wars of 1915 he served with Gen. Obregon in the cam paigns against Villa, and in 1917 became governor of Sonora. During his brief administration as governor he succeeded in establishing an industrial school at Hermosillo and in securing legislation favourable to labour and prohibition. He was minister of commerce, labour and industry under Carranza, secretary of war under the provisional Government of Adolfo de la Huerta and secretary of the interior under President Obregon. In 1924, as the candidate of the Labour Party, he was elected president for the four-year term ending Dec. I, 1928. President Calles came into power pledged to continue the work begun under Pres ident Obregon : land for the peasants, work for the workers, edu cation for the masses and legitimate profits for decent capital and honest business. The chief international problems of the adminis tration grew out of the alien land and petroleum laws passed by the Mexican Congress, at the president's request, in Dec. 1925 (see MEXICO: History). Early in Jan. 1926, just as a spirited diplomatic controversy with the United States concerning these laws reached an apparent crisis, the Mexican Roman Catholic episcopate took a positive stand against the religious and educa tional provisions of the Constitution and thus precipitated a con flict between church and State. A decision of the Mexican Supreme Court (Nov. 1927) declaring certain articles of the petroleum law unconstitutional and the diplomacy of Dwight Morrow, U.S. ambassador to Mexico, have brought about amicable relations between the two nations. The solution to the church question has proved more difficult. He was succeeded by Portes Gil.