The Gans family is a prominent German family of industrialists and philanthropists from Frankfurt am Main. It is descended from Ludwig Aaron Gans, a Jewish businessman from Celle, who became an apprentice in the firm Caßel & Reiß in Frankfurt in 1814. In 1828, he married Rosette Goldschmidt (1805–1868), a niece and adopted daughter of the firm's owner Leopold Cassella, and was accepted as a partner of the firm. In 1848, Gans became sole owner of Leopold Cassella & Co., as the company was then named. Ludwig Aaron Gans was the father of the major industrialist , who was ennobled in 1912, and of the chemist and industrialist . The family converted from Judaism to Protestantism in the late 19th century.