The Mafia, a criminal society, originated in Sicily when the large landowners put their estates into the hands of ruffianly "security men" during the disturbances which followed Napoleon's invasion of Italy. These men terrorized the peasantry, and finally turned on the landowners.
Their principles were never to appeal to the law and never to help in the detection of crime. By faithfully following their savage code, the Mafia soon became powerful not only in the country but in the towns. Successive Italian governments tried in vain to suppress it.
With European emigration to the United States during the last century, an organization similar to the Mafia came into being there, with the familiar set up of ruling families, infiltration of society, protection rackets, and bloody acts of vendetta and revenge.
Its heyday was probably the Prohibition era. But it is still believed to exert considerable influence in American life.