Joseph Rosenthal was born on October 9, 1911 in Washington, D.C. His parents were Russian Jewish immigrants; however, he converted to Catholicism during his youth. His interest in photography started as a hobby in San Francisco, California, during the Great Depression, where he lived with his brother while looking for work. He became a reporter-photographer for the San Francisco News in 1932. He is a graduate of the University of San Francisco.