In the summer of 1949. David Halberstam was 15, moving uncertainly into adolescence and looking longingly back over his shoulder at boyhood. America was struggling, too—one generation still emotionally chastened by the Depression, the other increasingly emboldened to expansion and entrepreneurship; the entire country’s culture and class structure splintered by immigration and nearly upended by the war. Only decades later did it occur to Halberstam that he and the country had both taken temporary refuge in one of the last pure flights of baseball fantasy: the down-to-the-wire penant race between Joe DiMaggio’s New York Yankee’s and Ted William’s Boston Red Sox.

And when he looked back to that summer, to the delicate intricacies of box scores and percentages and larger-than-life heroes and smaller-than-myth prejudices, he also saw in the Yankees/Red Sox struggle a rite of national passage.

"That was 40 years ago, but it might as well have been 100," Halberstam says now. "It was the last part of the radio era, before television transformed sports into ‘entertainment.’ It was radio instead of TV, trains instead of planes, it was day ball rather than night games, grass stadiums instead of Astroturf, a time when management was all-powerful rather than the athletes.

"It was an entirely white America, one just beginning to percolate. St. Louis was a Western city and Washington was a Southern one." And baseball truly was the Great American Pastime: "You didn’t have the Final Four, you didn’t have [a TV-fed national obsession with] pro football or the Super Bowl. Nobody had yet heard of Pete Rozelle."

Baseball represented not just competition, as did most sports, but life—no mere victory, but struggle. It required strategy; it offered inspiration; it provided escape and an equalizer for the hundreds of thousands of men and boys who poured over the box scores in taverns and by radios.

Even more fittingly, the pennant races of 1949 exemplified the great rivalry of American baseball, the celebrity-studded, image-conscious Yankees from the House That Ruth Built versus the boyish, beloved, heartbreaking Bosox—New England’s national team. It was the cigar-chomping, hard-driving Red Sox manager John McCarthy, remnant of a rougher age, versus glad-handing, deceptively simple Casey Stengel. It was the duel of a generation, and although they couldn’t have known it, it was also the beginning of the decline.

Of the two great journalistic styles of the post-Vietnam era, "new" and "gonzo," Halberstam’s method emphasized the causes while the flak attack of the Tom Wolfes and Hunter Thompsons seizes on effects. A book like Summer of ’49 plays to the strenghts of Halberstam’s "Best and Brightest" style: His character studies, carefully researched and enriched with revealing anecdotes, become three-dimensional baseball cards, as much snapshots of contemporary society as profiles of the ballplayers.

Here, for instance, is a portrait of the great DiMaggio, the most famous athlete in the United States and arguably the most famous man—a player so intense that he suffered from insomnia and ulcers, so excruciatingly awarre of his fans’ needs that he drove himself to play with extraordinary pain; a player who, finally sidelined with crippling bone spurs, suffered in self-impsosed exile in his hotel room and emerged in true heroic style in time to lead the second-half rally.

And here on the flip side is the bigger picture: the offhand ethnic slurs, the Life magazine story noting with surprise that DiMaggio never used bear grease or olive oil on his hair and "never reeks of garlic," the team nickname "the Dago" (wiry Phil Rizzuto was "Little Dago). DiMaggio was just one of the first generation athletes who found the American Dream on the American diamond (baseball commissioner Bart Giamatti, then 11, kept stats on his own all-Italian all-star lineup);; and many of DiMaggio’s fans who couldn’t even speak English smuggled Italian flags and banners into Yankee stadium and screamed for Joltin’ Joe.

Here also is Rizzuto, with his boy-sized glove and his horror of live animals; Yogi berra, the bricklayer’s son who was called too clumsy and too slow; Tommy Heinrich, who never forgot that baseball had liberated him from a $22.50-a-week typing job (and who, when signed to the New Orleans minor league team, intentionally wore his oldest clothes to the ballpark to avoid the temptation to carouse with his colleagues). And here is the obsessive Williams, who hated reporters as much as he loved hitting; Johnny Pesky, whose Croatian immigrant parents feared he’d shorten his name out of shame; the gentle Do, DiMaggio, both proud of his brother and inescapably overshadowed by him.

This is a wonderful look back at the last real "boys" of summer—the players and the boys and men who loved them, in a time when heroes still walked the earth and wore uniforms.

Eve Zibart is a staff writer for The Washington Post, where she doubles as "Dr. Nightlife."