(Mexico City, 1908 - 1985, Mexico City)
Born 1908, Mexico City; active late 1920s–34, California and New York; 1934–85, Mexico; died 1985, Mexico City
Arenal's family immigrated to the United States when he was young. He studied architecture and sculpture in Los Angeles and spent time a the University of Arizona in the 1920s. In 1932 Arenal learned the art of fresco painting from David Alfaro Siqueiros who was painting in Los Angeles at that time. Arenal assisted him on mural paintings at the Chouinard Art School in L.A. and continued to collaborate with him until Siqueiros' death in 1974. In 1939 Arenal and Siquerios executed a mural for the headquarters of the Electrical Worker's Union in Mexico City. In 1944-45 he completed two sculptures that form a unit with one of Siqueiros' murals (Cuauhtémoc contra el mito) at the Center of Modern Art in Mexico City. In 1933 Arenal returned to Mexico where he served as the General Secretary of the Mexican League Against War and Fascism. He was a founding member of LEAR and with Juan de la Cabasa helped to start its journal, Frente a frente. Arenal attended the New York Congress of American Artists in 1936 as a delegate for LEAR. He was a founding member of the TGP as well and participated in all of the group exhibitions, acting as coordinator of the workshop in 1965.