Born in Mexican revolution times, Pedro Armendáriz was the first child of Mexican Pedro Armendáriz García-Conde and American Adele Hastings. He was raised in Churubusco, then a suburb of Mexico City, before the family traveled to Laredo, Texas. They lived there until 1921, the year Armendáriz' parents died. His uncle Francisco took charge of his education, and young Pedro went to the Polytechnic Institute of San Luis Obispo, California. There, he studied business and journalism. He graduated in 1931 and returned to Mexico City where he found work as a railroad employee, insurance salesman and tourist guide. He was discovered by director Miguel Zacarías when Armendáriz was reciting Hamlet's monologue (to be or not to be) to an American tourist in a cafeteria.