Charles Korr doesn’t buy it. The End of Baseball As We Knew It, his history of the baseball players’ union, is an alternative take on the national pastime’s recent past, and required reading for anyone who’s tempted to jump on the anti-union bandwagon in this latest round of labor trouble. Korr, who was granted access to the Maj-or League Baseball Play-ers Association’s archives, chronicles the early years of the union that’s largely responsible for today’s professional sports landscape.

For those of us who grew up with millionaire superstars, the bad old days of baseball that form the backdrop of this book seem almost unimaginable. During the sport’s so-called Golden Age of the 1950s and ’60s, players worked under degrading conditions imposed by the owners. Clubs kept salaries low, and punished players who asked for more. Some of the era’s most famous players suffered heavy-handed treatment. In 1957, future Hall-of-Famer Mickey Mantle asked the New York Yankees for a raise after winning the American League Triple Crown. The team’s general manager responded by threatening to show Mantle’s wife a private detective’s dossier on the outfielder’s carousing nightlife if he didn’t accept the team’s offer. Mantle quickly caved. The 19th-century labor rules still in place in the ’50s left him with few options: The infamous “reserve clause” in players’ contracts forbade Mantle from seeking a better deal from another club. Black players suffered further humiliation during spring training, when many teams moved to segregated facilities in Florida. Players could be bought or sold on an owner’s whim. Job security was nonexistent; baseball is a remorselessly meritocratic business, and every player knew an injury or a hot rookie could end his career overnight.

The hero of Korr’s book is Marvin Miller, a young Steelworkers Union economist hired by the players in 1966 to play hardball with the owners. Miller was the union’s first full-time director, and the first to violate a baseball taboo by using the word “union.” Word of Miller’s hiring scandalized the sports press. In one of the more entertaining parts of his book, Korr catalogues the insults hurled at Miller by baseball beat writers, one of whom characterized him as “Marvin Millerinski,” a Bolshevik agent out to ruin America’s national pastime.

Korr methodically chronicles the series of union victories through the ’60s and ’70s, including the abolition of the reserve clause and introduction of free agency. But Miller’s most profound accomplishment was to change the way Americans think about sports. Fans and the press had a romantic image of their sports heroes as men who played for sheer love of the game (some still do). Korr sarcastically refers to this as the “aw, shucks, gee whiz, I’m so glad to be a major leaguer I’d pay to put on the uniform” stereotype. Miller quickly put an end to that. Depending on which reading of history you subscribe to, baseball either lost its innocence or finally grew up under Miller. The assertive players of his union insisted on controlling their own careers and getting a fair share of baseball’s considerable profits.

Baseball owners have been fighting a losing battle ever since. In 1966, many of them were successful in other fields and owned a baseball team for prestige or for fun. Owners like Gussie Busch of the St. Louis Cardinals considered themselves patrons of an American folk art, rather than businessmen. This is a problem that continues to vex baseball management; some of the owners still have yet to decide whether they are “capitalists or hobbyists,” as David Halberstam put it in a recent ESPN column. Meanwhile, capitalism has spread to the other American pro sports.

Korr’s history ends before the current round of baseball turmoil, but the themes in the game’s labor wars have stayed largely the same over three decades. Since its founding, the union has staked itself to the position that players ought to be paid what they’re worth in an all-American free market. Owners have looked for ways to limit player salaries for just as long. It’s hard to sympathize with millionaire baseball players, but harder still to sympathize with billionaire owners. As for the pessimistic predictions and yearning for the Golden Age that dominate today’s sports pages, they’re best thought of as an occupational hazard in an industry that trades on nostalgia, epitomized by quotes such as this one: “Players make too much money and become spoiled.” That was in 1915.