The Warburg family is a prominent German and American banking family of German Jewish and originally Venetian Jewish descent, noted for their varied accomplishments in biochemistry, botany, political activism, economics, investment banking, law, physics, classical music, art history, pharmacology, physiology, finance, private equity and philanthropy. They are thought to have originated as the Venetian Jewish del Banco family, Anselmo and Abraham Ha Levi Kahana de Palenzuela from Spain, one of the wealthiest Sephardic German families in the early 16th century. Due to restrictions limiting Jewish involvement in banking, they moved to Bologna, and thence to Warburg, in Germany, in the 16th century, after which they later took their name. The first known ancestor was Simon von Kassel (1500 - 1566). The family later established itself in Altona, near Hamburg in the 17th century, after the Thirty Years' War, and it was in Hamburg that M. M. Warburg & Co. was established in 1798, among the oldest still existing investment banks in the world. Other banks created by members of the family include M.M.Warburg & Co.; Warburg Pincus; and S. G. Warburg & Co., renamed UBS Warburg in 1995, following its acquisition by UBS. Family organization Alsterufer and Mittelweg lines The family is traditionally divided into two prominent lines, the Alsterufer Warburgs and the Mittelweg Warburgs. The Alsterufer Warburgs descended from Siegmund Warburg (1835–1889) and the Mittelweg Warburgs descended from his brother Moritz M. Warburg (1838–1910). They took their nicknames from the brothers' respective addresses in Hamburg's Rotherbaum neighborhood. The brothers were grandsons of Moses Marcus Warburg. Siegmund George Warburg was of the Alsterufer lines; the five brothers Abraham (Aby) M., Max M., Paul M., Felix M. and Fritz Moritz Warburg were of the Mittelweg line. The brothers Moses Marcus Warburg (1763–1830) and Gerson Warburg (1765–1826) founded the M. M. Warburg & Co. banking company in 1798. Moses Warburg's great-great grandson, Siegmund George Warburg, founded the investment bank S. G. Warburg & Co in London in 1946. Siegmund's second cousin, Eric Warburg, founded Warburg Pincus in New York in 1938. Eric Warburg's son Max Warburg Jr. (not to be confused with Eric's father Max Warburg) is currently one of the three partners of M.M.Warburg & Co., Warburg. Max Warburg's elder brother Aby Warburg used family resources to establish the Kulturwissenschaftliche Bibliothek Warburg in Hamburg, since 1934 The Warburg Institute in London. Paul Warburg is most famous as an architect of the