“Aren’t you crushed in the crowd? . . . Aren’t you bothered by the noise. . . ? Yet you seem to put up with all this gladly when you think of the gripping feats you will see.” More than 2,000 years separate us from that ancient Olympics fan, but nowadays, the feats are just as gripping — and easier to observe: Every event and awards ceremony of the London Olympics will be live-streamed this summer. In his new history, “A Passion for Victory,” Benson Bobrick entertainingly conveys the many other ways the Games have changed since ancient times: The all-male contestants performed in the nude, married women were not allowed to watch and false starts were punished with an official’s whip. Young readers will get a sense of the ways religion and militarism pervaded the early incarnation of the Olympics, which, astoundingly, was held regularly for about a millennium; in the modern era, the Games have been interrupted by world wars and Cold War boycotts. Throughout this well-illustrated chronicle, which Bobrick takes up to the 1948 Games, Olympic spectators and competitors are vividly drawn, from the philosopher-wrestler Plato, whose nickname meant “fatso,” to more recent heroes, such as Jim Thorpe and Jesse Owens. Who will be the new Olympic icons? Let the Games begin again!