Question: The Cohen crime family, or the Siegel crime syndicate, was an Italian-American Mafia / Jewish Mafia crime family created by which New York Jewish American mobster, and was known as one of the most "infamous and feared gangsters of his day"?
Context: The Bufalino crime family, also known as the Pittston crime family, Scranton Wilkes-Barre family, Northeastern Pennsylvania crime family, Northeastern Pennsylvania Mafia, or Scranton Mafia is an Italian-American Mafia crime family active in the Northeastern Pennsylvania cities of Scranton, Wilkes-Barre, and Pittston. The Patriarca crime family (pronounced ] ) is also known as the New England crime family, the Providence crime family, the Boston crime family, the Boston Mafia, the Providence Mafia, the New England Mafia, or The Office and is an Italian-American Mafia crime family based in New England.  The crime family has two distinct factions, one active in Providence, Rhode Island and the other in Boston, Massachusetts. The San Francisco crime family, also known as the Lanza crime family, was an American Mafia crime syndicate in San Francisco.  The syndicate was organized in the early 1930s by Francesco "Frank" Lanza.  The San Francisco family was a small organization with 20–25 made members. A caporegime or capodecina, usually shortened to just a capo, is a rank used in the Mafia (both the Sicilian Mafia and Italian-American Mafia) for a "made member" of the crime family who heads a "crew" of soldiers and has major social status and influence in the organization.  Caporegime is an Italian word, which is used to signify the head of a family in Sicily, but has now come to mean a ranking member, similar to captain or senior sergeant in a military unit.  In general, the term indicates the head of a branch of an organized crime syndicate who commands a crew of soldiers and reports directly to the Don (Boss) or an Underboss or Streetboss. The Cohen crime family, or the Siegel crime syndicate, was an Italian-American Mafia / Jewish Mafia crime family created by New York Jewish American mobster Benjamin "Bugsy" Siegel in the early 1930s.  Siegel ran Los Angeles and later Las Vegas' illegal gambling and prostitution rings with his lieutenants Mickey Cohen, David Berman, Harold "Hooky" Rothman, Moe Sedway and boss of the L.A. family Jack Dragna. Benjamin "Bugsy" Siegel (February 28, 1906 – June 20, 1947) was a Jewish American mobster.  Siegel was known as one of the most "infamous and feared gangsters of his day".  Described as handsome and charismatic, he became one of the first front-page celebrity gangsters.  He was also a driving force behind the development of the Las Vegas Strip.  Siegel was not only influential within the Jewish mob but, like his friend and fellow gangster Meyer Lansky, he also held significant influence within the Italian-American Mafia and the largely Italian-Jewish National Crime Syndicate. Girolomo "Momo" Adamo (1895–1956) was an Italian American mobster in the American Mafia.  He lived in Chicago and Kansas City before moving to Los Angeles in the 1930s and soon became underboss to Jack Dragna in the Los Angeles crime family.  His brother Joseph Adamo was also a member of the crime family.  Both he and his brother were well connected criminals in San Diego, working with such mobsters as Frank Bompensiero.  In 1950, Momo was arrested along with several members of Jack Dragna's family including Tom Dragna (brother), Louis Dragna (nephew), and two men named Frank Paul Dragna (his son and nephew, respectively) after Jack fled the state after being named in the California Crime Commission report as a member of a crime syndicate in Los Angeles.  The five of them were taken into custody by the Los Angeles Police Department, who believed they were responsible for bombing Mickey Cohen's home or knew who was.  They were all released without being charged when the police couldn't find evidence of their involvement (Tom built the bomb, but otherwise none of them were involved). William "Wild Guy" Grasso was an Italian-American gangster from East Haven, Connecticut who served as underboss to Raymond Patriarca, Jr. (a.k.a. "Junior") in the Patriarca crime family, also known as the New England crime family, the Providence crime family or the Boston crime family.  The Patriarca family is a Mafia crime family based in New England.  Succeeding his father Raymond L.S. Patriarca as boss after his father's death in 1984, Junior was considered a weak leader.  He managed to keep the peace in his crime family due to the support of the Gambino crime family of New York.  When Junior's original underboss Ilario "Larry Baione" Maria Antonio Zannino was sentenced to thirty years in prison in 1987, it further weakened Junior's position.  With Zannino in jail, Grasso became underboss. The East Harlem Purple Gang was a semi-independent gang of Italian American hit-men and heroin dealers who, according to federal prosecutors, dominated heroin distribution in East Harlem and the Bronx during the late 1970s and early 1980s in New York City.  Though mostly independent of the Italian-American Mafia and not an official Italian-American Mafia crew, the gang was originally affiliated with and worked with the Lucchese crime family and later with the Bonanno crime family and Genovese crime family.  It developed its "closest ties" with the Genovese family, and its remnants or former members are now part of the Genovese family's 116th Street Crew. The Cohen crime family, or the Siegel-Cohen crime syndicate, was a Jewish-Italian crime family that was active from 1933 to 1961.  The family was founded by New York Jewish mobster Benjamin "Bugsy" Siegel in the early 1930s.  He had Los Angeles Mafia boss Jack Dragna and Jewish mobsters Mickey Cohen and Moe Sedway as his lieutenants.  He created the biggest prostitution ring, gambling and protection rackets in Las Vegas and Los Angeles.  He also expanded into drug trafficking and bookmaking.
Answer: Benjamin "Bugsy" Siegel