August Belmont, Sr. (December 8, 1813 – November 24, 1890) was an American politician.
August Belmont was born in Alzey, Hesse, on December 8, 1813--some sources say 1816--to Simon and Frederika Elsass Schönberg, a Jewish family. After his mother's death, when he was seven, he lived with his uncle and grandmother in Frankfurt. He attended the Jewish Junior and Senior High School until he began his first job as an apprentice to the Rothschilds. He would sweep floors, polish furniture, and run errands while studying English, arithmetic, and writing. He was then given a confidential clerkship in 1832 and promoted to private secretary before travelling to Naples, Paris, and Rome. In 1837, Belmont set sail for Havana charged with the Rothschild's Cuban interests. On his way to Havana, however, Belmont stopped in New York. He arrived there during the Panic of 1837 and then remained to supervise jeopardised Rothschild interests there instead of continuing on to Havana. After he emigrated to the United States, he changed his surname, Schönberg (German for "beautiful mountain"), to Belmont (French for "beautiful mountain").