Lazaro Cardenas del Rio. A leader emerged in Mexico as the blood, violence and terror of the Mexican Revolution subsided. Lázaro Cárdenas del Rio had fought under Obregón and had seen his political star rise in the 1920's. His reputation for honesty served him well, and when he took over for the crooked Plutarco Elias Calles in 1934, he quickly began cleaning house, tossing out many corrupt politicians (including Calles). He was a strong, able leader when his country needed it the most.