Background: Undercover detective with a network of secret agents

ALLAN Pinkerton has become one of America's most famous Scots. He foiled an attempt to assassinate the abolitionist president Abraham Lincoln, and during the American Civil War he organised the Union Intelligence Service, the forerunner of the American Secret Service. He had a network of spies in the South and worked undercover himself.

Later he was hired to track down Jesse James, but that proved difficult, partly because James was seen as a folk hero. When the railway company dispensed with his services, he continued his hunt at his own expense.

Expanding overseas, he worked for the Spanish colonial authorities in Cuba, even though the rebels were campaigning for democracy and an end to slavery. He also wrote detective fiction.

In 1884 Pinkerton fell and bit his tongue, which became infected and he died as a result. At the time he was working on a national catalogue of criminals, the basis for the FBI's database.

After his death, his sons continued in the business and the agency became associated with big business and violent strike-breaking tactics.

Pinkertons still exists, and now has offices all over the world.