He played a major role in the growth and the development of the union, which eventually became the largest by membership in the United States, with over 2.3 million members at its peak, during his terms as its leader.

Hoffa married Josephine Poszywak, an 18-year-old Detroit laundry worker of Polish heritage, in Bowling Green, Ohio, on September 25, 1937.

By 1932, after refusing to work for an abusive shift foreman, Hoffa left the grocery chain, partly because of his union activities.

[12][15] In 1952, a petty criminal living in New York, Marvin Elkind, was assigned by gangster Anthony Salerno to work as Hoffa's chauffeur.

[20] Beck, his predecessor, had appeared before the John L. McClellan-led US Senate Select Committee on Improper Activities in Labor or Management Field in March 1957 and took the Fifth Amendment 140 times.

[26] In 1964, he succeeded in bringing virtually all over-the-road truck drivers in North America under a single National Master Freight Agreement, which may have been his biggest achievement in a lifetime of union activity.

[12] Hoffa was re-elected without opposition to a third five-year term as president of the IBT, despite having been convicted of jury tampering and mail fraud in court verdicts that were stayed pending review on appeal.

As attorney general from 1961, Kennedy pursued a strong attack on organized crime and he carried on with a so-called "Get Hoffa" squad of prosecutors and investigators.

[32][33] In May 1963, Hoffa was indicted for jury tampering in Tennessee, charged with the attempted bribery of a grand juror during his 1962 conspiracy trial in Nashville.

[37] As a result of Hoffa's previous resignation, he was awarded a $1.75 million lump sum termination benefit by the Teamsters Retirement and Family Protection Plan.

[35][44] Hoffa accused senior Nixon administration figures, including Attorney General John N. Mitchell and White House Special Counsel Charles Colson, of depriving him of his rights by imposing that condition.

[52] At the time of his death, Hoffa lived with his family at their summer cottage in the village of Lake Orion, which was about a half hour drive from the restaurant where he was last seen.

"[12] Hoffa left his Lake Orion home at 1:15 p.m. Before heading to the restaurant, he stopped at the Pontiac office of his close friend Louis Linteau, a former president of Teamsters Local 614 who now ran a limousine service.

[68][69] Between 2:15 and 2:30 p.m., an annoyed Hoffa called his wife from a payphone on a post in front of Damman Hardware, directly behind the Machus Red Fox, and complained that Giacalone had not shown up and that he had been stood up.

[77] The primary piece of physical evidence obtained in the investigation was a maroon 1975 Mercury Marquis Brougham, which belonged to Anthony Giacalone's son, Joseph.

[83] Despite extensive surveillance and bugging, investigators found that the Mafia members were generally unwilling to talk about Hoffa's disappearance, even in private.

[84] In October 1975, Michigan Attorney General Frank J. Kelley went to Waterford Township to supervise an unsuccessful expedition to locate and exhume Hoffa's remains.

Although not claiming conclusively to establish the specifics of his disappearance, the memo records a belief that Hoffa was murdered at the behest of organized crime figures, who regarded his efforts to regain power in the Teamsters as a threat to their control of the union's pension fund.

The Hoffex Memo noted that Provenzano was not senior enough to order a Mafia hit, though it did not rule out the possibility that his or someone else's personal vendetta against Hoffa was a motive.

[92] Scott Burnstein, a crime historian and journalist, argued in 2019 that Provenzano's role in the entire case was limited to acting as a lure.

He argued that Hoffa had no realistic prospects for a comeback, that the disappearance did not share the usual characteristics of a Mafia hit and that it risked encouraging action against organized crime (as indeed happened).

[95] In his 1991 book Hoffa, Arthur A. Sloane said that the most common theory of FBI investigators was that Russell Bufalino was the mob boss who ordered the murder, and Salvatore "Sally Bugs" Briguglio, his brother Gabriel Briguglio, Thomas Andretta and Charles "Chuckie" O'Brien were the men who lured Hoffa away from the restaurant.

[96] Sloane listed a local waste incinerator and a landfill in Jersey City as the possible locations where the body was taken;[91] the latter is also supported by Dan Moldea.

[103] In one of his jailhouse confessions published in a biography released after his death in 2006, Richard Kuklinski claimed that he was part of a four-man team who kidnapped and murdered Hoffa.

[105][106] In 2012, Roseville, Michigan, police took samples from the ground under a suburban Detroit driveway after a person reported having witnessed the burial of a body there around the time of Hoffa's 1975 disappearance.

[108] In January 2013, the reputed gangster Tony Zerilli, implied that Hoffa was originally buried in a shallow grave, with plans to move his remains later to a second location.

"[112] In an April 2019 interview with DJ Vlad, the former Colombo crime family capo Michael Franzese stated that he was certain that Hoffa's disappearance had been mob-related.

[1] Arthur Sloane wrote, "To many, Hoffa was a kind of latter-day Al Capone... others, he was... hugely successful in improving working conditions for [his truck-driver constituents].

[123] In the Sergio Leone film Once Upon a Time in America (1984), syndicalist James Conway O'Donnell's character, played by Treat Williams, is inspired by Hoffa.

[124] In the comedy film Bruce Almighty (2003), the titular character uses powers endowed by God to manifest Hoffa's body in order to procure a story interesting enough to reclaim his career in the news industry.