EVERYWHERE David Montgomery went, the FBI was right behind him.

He would get a job in a factory and the FBI would get him fired. He tried smaller factories, but the FBI always tracked him down and got him fired.

Why? Because David Montgomery was a communist labor organizer for the machinists union in the dark days of McCarthyism in the '50s - and J. Edgar Hoover didn't like commies.

At Minneapolis Honeywell, the company had to shut down an entire division to fire him because the workers felt that "an injury to one was an injury to all."

Finally, David wound up in a shop with only one other worker.

"I organized that guy into the union," he told blogger Jon Wiener, "and the FBI didn't get me fired."

However, he said, "I realized they had me beat, so I quit and became a historian."

David Montgomery, a Bryn Mawr native who eventually renounced communism when the Soviet Union crushed the Hungarian rebellion in 1956, wrote extensively about labor conditions in the U.S., using his experience on the factory floor to lend credence to his writings.

He died Dec. 2 of a brain hemorrhage. He was 84 and lived in Kennett Square.

David taught at the University of Pittsburgh and at Yale University, and wrote several books about the lives of workers, their interactions, social networks, relations with superiors and so forth.

His books include Beyond Equality: Labor and the Radical Republicans, 1862-1872; Workers' Control in America: Studies in the History of Work Technology and Labor Struggles, and his major effort, The Fall of the House of Labor: The Workplace, the State and American Labor Activism, 1865-1925.

Bruce Weber, in a New York Times obituary, wrote that David "created vivid pictures of workers in the iron foundries, steel plants and munitions and electrical equipment factories of the 19th and early 20th centuries."

David graduated from the Haverford School. He served in the Army in Los Alamos, N.M., as World War II was ending, then returned to the Philadelphia area and graduated from Swarthmore College.

After his experience working as a machinist and labor organizer in factories in New York and Minneapolis - and ducking the FBI - he returned to academia, earning a master's and doctorate, both in history, from the University of Minnesota.

Along with other historians, he altered the teaching of labor issues from a purely economic viewpoint to a focus on putting "social drama and moral seriousness back into the struggles of labor, not just the great strikes of Homestead and Ludlow, but also into the seemingly mundane conflicts over a change in work rules, or a 5-cent wage advance," as a critic put it.

Even after he entered academia, David didn't lose his passion for workers' rights. He loudly supported the campus clerical workers at Yale in a 1984 strike.

"David was never shy about demonstrating the relationship between his scholarship and active commitment," Shelton Stromquist, professor of labor history at the University of Iowa and a former student of David's at Pitt, told the New York Times.

David married the former Martel Wilcher in 1952. Besides her, he is survived by two sons, Edward and Claude; a brother, Daniel; a sister, Virginia Baily, and five grandchildren.