Arnold Rothstein, nicknamed "The Brain", was an American racketeer, crime boss, businessman, and gambler who became a kingpin of the Jewish Mob in New York City. Rothstein was widely reputed to have organized corruption in professional athletics, including conspiring to fix the 1919 World Series. He was also a mentor of future crime bosses Lucky Luciano, Meyer Lansky, Frank Costello, Bugsy Siegel, and numerous others.

Jewish-American organized crime initially emerged within the American Jewish community during the late 19th and early 20th centuries. In media and popular culture, it has variously been referred to as the Jewish Mob, the Jewish Mafia, the Kosher Mob, the Kosher Mafia, the Yiddish Connection, and Kosher Nostra or Undzer Shtik. The last two of these terms are direct references to the Italian cosa nostra; the former is a play on the word for kosher, referring to Jewish dietary laws, while the latter is a calque of the Italian phrase 'cosa nostra' into Yiddish, which was at the time the predominant language of the Jewish diaspora in the United States.