Capone and the Krays

Mafia groups in the United States first became influential in the New York City area, gradually progressing from small neighborhood operations to citywide and eventually international organizations. The mafia started when a group called "The Black Hand" vandalised Italian (and other immigrant) neighborhoods all around New York city. The Black Hand would attack anyone prosperous in the neighborhood, and usually threaten them by mail. They would sign it with a hand covered in black ink at the bottom of the page. As many gangs started, the Italians built a retaliation gang, which eventually exterminated the Black Hand and started doing other crimes than retaliation, such as robbery, which then progressed to murder, kidnappings, and extortion.

The Mafia had eventually expanded to twenty-six crime families nationwide in the major cities of the United States, with the center of organized crime based in New York. After many turf wars, the Five Families ended up dominating New York, named after prominent early members: the Bonanno family, the Colombo family, the Gambino family, the Genovese family, and the Lucchese family. These families held underground conferences with other mafia notables like Joe Porrello of Cleveland, and other gang leaders, such as Al Capone.

Each family was ultimately controlled by a Don, who was insulated from actual operations by several layers of authority. According to popular belief, the Don's closest and most trusted advisor was referred to as the consigliere ("counselor" in Italian). In reality, the consigliere was meant to be something of a "hearing officer" who was charged with mediating intra-family disputes. He also takes care of the economic side of the "business". An underboss was possible as well. The "underboss guard" was a position between the consigliere and underboss, providing tactical information as well as advice to the boss. There were then a number of regimes with a varying number of soldati (lit. "soldiers"), or "made" men, who conducted actual operations. Most recently there have been two new positions in the family leadership, the family messenger and Street Boss. These positions were created by former Genovese leader Vincent Gigante.

Each faction was headed by a caporegime, who reported to the boss. When the boss made a decision, he never issued orders directly to the soldiers who would carry it out, but instead passed instructions down through the chain of command. In this way, the higher levels of the organization were effectively insulated from incrimination if a lower level member should be captured by law enforcement. This structure is depicted in Mario Puzo's famous novel The Godfather.

The initiation ritual emerged from various sources, such as Catholic confraternities and Masonic Lodges in mid-nineteenth century Sicily and has hardly changed to this day. The Chief of Police of Palermo in 1875 reported that the man of honor to be initiated would be led into the presence of a group of bosses and underbosses. One of these men would prick the initiate's arm or hand and tell him to smear the blood onto a sacred image, usually a saint. The oath of loyalty would be taken as the image was burned and scattered, thus symbolising the annihilation of traitors. This was confirmed by the first pentito, Tommaso Buscetta.

A hit, or assassination, of a "made" man had to be preapproved by the leadership of his family, or retaliatory hits would be made, possibly inciting a war. In a state of war, families would go to the mattresses — rent vacant apartments and have a number of soldiers sleeping on mattresses on the floor in shifts, with the others ready at the windows to fire at members of rival families.

The American Mafia eventually became more accommodating of non-Sicilian Italians among the sworn-in membership of "made" men and forged closer associations with gangsters of other nationalities, thus becoming distinct from the original organization in Sicily.