Although he never received a high school diploma, Fiorello La Guardia studied law at New York University and was admitted to the New York bar in 1910. He was elected to the U.S. Congress as a Republican in 1916. Following service in World War I and as president of the New York City Board of Aldermen, he returned to Congress from 1923-1933. There he defended the interests of his predominantly immigrant, working-class constituency. He condemned legislation establishing national-origin quotas for the admission of immigrants. La Guardia was elected mayor of New York in 1933 and served through 1945. As mayor he fought political corruption and introduced improvements in the fields of health, housing, recreation, and the arts.