Pinkerton (detective agency)

Pinkerton, founded as the Pinkerton National Detective Agency, is a private security guard and detective agency created in the United States by Scottish-American spy Allan Pinkerton in 1850. It is a part of Securitas AB. 
Pinkerton became famous when he claimed to have stopped a plot to assassinate president-elect Abraham Lincoln, who later hired Pinkerton agents for his personal security during the Civil War. Pinkerton's agents performed services ranging from security guarding to private military contracting work. 
The Pinkerton National Detective Agency hired women and minorities from its founding. Pinkerton was the largest private law enforcement organization in the world at the height of its power.