The 18th Amendment to the Constitution was ratified in 1919 and went into effect in 1920. A huge win for temperance advocates, the new law made alcoholic beverages illegal in America. But it didn't take long for the federal government to realize enforcing the ban would be difficult. Bootlegging, or illegally manufacturing and selling liquor, became a common business venture for willing entrepreneurs. Speakeasies and rum-runners made millions selling illegal alcohol -- and bootlegging gang organizations made even more. Some bootleggers became notorious and their fame outlasted the prohibition law itself, which ended in 1933 with the repeal of the 18th Amendment.

Al "Scarface" Capone: Public Enemy Number One

Capitalizing on bootlegging opportunities, Al Capone created a hugely successful crime empire called the South Side Gang. His allies filled vice industry posts throughout the country. In Chicago, he gained control over massive networks of bookies, brothels, race tracks, clubs, speakeasies and distilleries. By 1925, his income swelled to more than $100 million a year. So wealthy, he "out-gunned" law enforcement. Capone was listed as "Public Enemy Number One" in 1930. In 1931, he was found guilty of tax evasion and sent to the Alcatraz Correctional Facility in 1932.

George “Bugs” Moran: North Side Gang Boss

At the beginning of the Prohibition era, George "Bugs" Moran worked as a leader in the infamous North Side Gang of Chicago. When its chief, Dean O'Bannion died in 1920, Moran took the reins and built a bootlegging empire. Though Moran was hugely successful in his own right, he is most recognized for his connection to Al Capone. He and Capone clashed in a gang war that took many civilian lives. The bloody battles continued for years until Capone's gang murdered nearly all of Moran's top men in the St. Valentine's Day Massacre of 1929.

George Remus: Attorney Turned Successful Bootlegger

George Remus had been a skilled defense attorney in the Midwest for 20 years when he decided that bootlegging would be a more lucrative enterprise. When Prohibition was enacted, he purchased local distilleries and created a drug company. He worked as buyer and seller and then cooked the books to "lose" shipments. His fortune amassed so quickly that he soon had 3,000 employees working for him. His business and legal savvy helped him rake in millions of dollars until his indictment for violating the National Prohibition Act in 1925. Remus would go on to kill his wife when he got out of prison, however, he was found not guilty on grounds of insanity.

Roy Olmstead: King of the Puget Sound Bootleggers

Roy Olmstead was an officer with the Seattle Police Department when he founded his bootlegging empire. In March of 1920, he was caught and his badge revoked -- but not before he learned valuable bootlegging information. With little competition and geography that made enforcement difficult, his empire quickly grew. Olmstead reportedly made over $200,000 a month and quickly became one of the biggest employers in the region. His bootlegging success continued until he and 89 other defendants were found guilty of violating prohibition laws in 1925. The case was America's largest trial under the 18th Amendment.