The Pinkertons were a famous and controversial private detective and security agency that played a big role in 19th‑ and early 20th‑century American history. They started as railroad detectives and ended up known both for crime fighting and for violently opposing labor unions.

Quick Scoop

  • The Pinkerton National Detective Agency was founded around 1850 in Chicago by Scottish immigrant Allan Pinkerton (with attorney Edward Rucker), originally as the North-Western Police Agency. It grew into the largest private law‑enforcement outfit in the world by the late 1800s.
  • Early on, they specialized in protecting railroads, preventing theft, and hunting train robbers and counterfeiters, which made them popular with big business.
  • The agency became famous after claiming to foil the 1861 “Baltimore Plot,” an alleged plan to assassinate President‑elect Abraham Lincoln on his way to Washington.
  • During the American Civil War, Pinkerton agents did espionage work for the Union and helped guard Lincoln, making them early forerunners of a federal secret‑service style role.

Work, methods, and “firsts”

  • The Pinkertons built one of the world’s largest collections of mugshots and criminal records at the time, effectively an early centralized criminal database.
  • They were hired to pursue famous outlaws like Jesse James, Butch Cassidy, and the Sundance Kid, becoming part of Old West legend and later pop‑culture.
  • The agency also stood out because it hired women and minorities as detectives relatively early, using them as undercover operatives when that was uncommon in mainstream police forces.

Why they’re controversial

  • By the late 19th century, Pinkertons were widely hired as strikebreakers and private muscle for big corporations, especially in mining, steel, and railroads.
  • Their role in violently confronting workers during major labor disputes—most notoriously the 1892 Homestead Strike in Pennsylvania—cemented their reputation among many as anti‑union enforcers rather than neutral detectives.
  • Because the agency at one point had more armed agents than the standing U.S. Army, some states (like Ohio) passed laws restricting or banning them as a potential “private army.”

How people see them today

  • Historically, some portray the Pinkertons as crime‑fighting pioneers who professionalized private investigation and security in an era when public policing was limited.
  • Others, especially in labor and left‑leaning spaces, remember them primarily as hired thugs for capital who spied on and violently repressed workers’ movements, a view still common in modern forum discussions criticizing their legacy.
  • The company still exists today as a global corporate security and investigations firm, now owned by the Swedish security giant Securitas AB, but its 19th‑century history is what keeps it a trending topic in media, podcasts, and online forums.

Information gathered from public forums or data available on the internet and portrayed here.