Edward "Monk" Eastman was an American gangster who founded and led the Eastman Gang in the late 19th and early 20th century; it became one of the most powerful street gangs in the city. His aliases included Joseph "Joe" Morris, Joe Marvin, William "Bill" Delaney, and Edward "Eddie" Delaney. Eastman is considered to be one of the last of the 19th-century New York City gangsters who preceded the rise of Arnold Rothstein and the Jewish mob. Later, more sophisticated, organized criminal enterprises also included the Italian American Cosa Nostra.

The Eastman Gang was the last of New York's street gangs which dominated the city's underworld during the late 1890s until the early 1910s. Along with the Five Points Gang under Italian-American Paolo Antonio Vaccarelli, best known as Paul Kelly, the Eastman gang succeeded the long dominant Whyos as the first non-Irish street gang to gain prominence in the underworld during the 1890s. Its rise marked the beginning of a forty to fifty-year period of strong Jewish-American influence within organized crime in New York City.