Final answer:
Pinkerton Detectives are most famous for their involvement in labor disputes such as the Homestead Strike of 1892, where their confrontation with steel workers led to multiple fatalities.
Step-by-step explanation:
The Pinkerton Detectives were best known for their role in labor disputes during the late 19th and early 20th centuries. One key event that highlights their notoriety was the Homestead Strike of 1892, where they were hired by the Carnegie Steel Company to protect company property during a lockout of union workers. On July 6, as the Pinkertons arrived on barges, a violent confrontation ensued with the unionized steel workers, resulting in the deaths of three Pinkertons and six workers.