(FORTUNE Magazine) – The brief history of entertainment in 20th-century America goes something like this: In the beginning, there was light; at the end, there was Armageddon.

The year 1900 began with a new art form, film, fluttering gently upon a screen. But now, as the entertainment business lumbers toward the next century, it has evolved into a full-blown industrial complex. Armageddon, after all, wasn't just a movie--it was a book, an Aerosmith-powered soundtrack, and a Walt Disney World exhibit, and in due time it will no doubt be deployed to boost ABC's ratings during a sweeps month. And yet the basic product has remained much the same through the century: Unlike the auto, food, or housing industries, entertainment doesn't provide necessities--it simply promises that, for a given fee, it will supply delight. (Technically speaking, of course, it also generates its fair share of delight's natural byproduct, disappointment, which can be found in such places as the 7:15 show of Wild Wild West.) It takes a certain magic to convert base materials into joy and then convert that joy into cash. The following individuals had just that ability. Conveniently, one of them was even named God.

The greatest of the early movie moguls, Louis B. Mayer was born on July 4, 1885, in Minsk. Or not. Like many in the entertainment industry, Mayer's creative output didn't stop at the office: He claimed he didn't know his birthday, so he simply appropriated that of his adopted country; his birth name was, in all likelihood, Lazar. Mayer started out as a theater owner in 1907 and went on to distribute films and then to produce them. In 1924 he joined the newly formed entity of Metro-Goldwyn as a vice president; within two years the studio bore his name as well. At MGM, Mayer perfected the studio system of moviemaking: Under his auspices (and, for a time, those of his Wunderkind production chief, Irving Thalberg), the studio produced stars the way Henry Ford made cars, and packaged them in a series of glossy, almost surreal fantasias of love and money--Grand Hotel, The Great Ziegfeld, Redheaded Woman. As a result, MGM became the top studio of the '30s and '40s, and Mayer himself pulled down a $1 million-plus annual salary even in the depths of the Depression, making him, for nine years running, the highest-paid man in America.

Jack Warner, by contrast, was never the highest-paid man in America. The studio he ran with his brother, Harry, was as cheap as MGM was profligate. The story goes that one day the actress Ann Sheridan was showing an actor around the Warner Bros. lot; they observed an older gentleman picking up nails off the floor and putting them in his mouth. "Who's that man and what's he doing?" the actor asked. "His name is Harry Warner," Sheridan replied, "and he happens to be the president of the company." But cheap as they were, the Warners managed to make one major contribution to the history of film. (Two, counting Casablanca.) In 1927, as their studio swooned on the edge of bankruptcy, the brothers released The Jazz Singer, the first feature-length "talkie." With nothing left to lose, the Warners had overcome the skepticism that had kept other studio chiefs from investing heavily in sound. (Mayer, for instance, huffed, "Let them develop it if they can. Then we'll see about it.") The talkie technology killed silent films--and at least one silent-film actor--even as it saved Warner Bros. from extinction. The studio survived to become part of Time Warner, owner of, among other things, FORTUNE.

The sound revolution rewrote movie history in ways small and large. Had it not been for The Jazz Singer, for instance, the first Mickey Mouse short would have been known to history as "Plane Crazy" rather than "Steamboat Willie"--if, that is, it would have been known at all. Walt Disney, then 25, had completed Mickey's first two vehicles, "Plane Crazy" and "Gallopin' Gaucho," both silent shorts, when word of the new sound technology reached him. He immediately started adding sound to his next project, "Steamboat Willie"--even providing Mickey's voice--and released it first. "Steamboat Willie" made Mickey a star; the mouse even won a special Academy Award for his creator in 1932. Seven years later Snow White and the Seven Dwarfs, the first feature-length animated film, earned Disney another Oscar--and inaugurated what is probably the most successful franchise in entertainment history, the Disney feature films. (The most successful of these, 1994's The Lion King, generated $1 billion in profits.)

In 1955, having established his studio as the premiere family brand in film, Disney expanded his purview with the launch of Disneyland, whose safe, sanitized attractions stood in stark contrast to the seamy thrills of carnival midways. It has since been joined by parks in Orlando, Tokyo, and Paris, which together made $5.5 billion last year. By arriving first and insisting on high standards of quality, Disney became the leader in family entertainment, a title that his company has yet to relinquish--Rugrats notwithstanding.

If Disney is now the best-known name in entertainment, few would recognize that of Goddard Lieberson--or, as he liked to sign his correspondence, "God." Lieberson served as CBS Records' president from 1956 to 1966 and again, briefly, in the 1970s. Trained as a classical pianist, he believed that "musicians make the best businessmen. I'd much rather be represented in a business deal by Stravinsky than any lawyer you could name."

Certainly his own innovations at CBS Records changed not only the way people listened to music but the scale of the entire industry. His first coup came in 1949, when he backed the successful introduction of the long-playing record, invented by Peter Goldmark. No longer were albums confined to fragile, four-minute 78s; now whole symphonies were contained on a single, durable vinyl disk. Lieberson, then the label's executive vice president, didn't stop at introducing the new format: He also produced its first smash hit, the original cast recording of South Pacific, and later, megasellers such as the original cast recording of My Fair Lady. And he trotted out a hit parade of easy-listening favorites, overseen by his chief artists-and-repertory man, sing-along legend Mitch Miller.

Lieberson was not, however, a fan of rock & roll, and CBS was late in realizing the music's power. But once it did, the crew recruited by Lieberson brought in diverse talents like Aretha Franklin, Bob Dylan, and Bruce Springsteen. And, if all that weren't enough, Lieberson also launched the Columbia Record Club and is thus responsible (for good or ill) for the 12-records-for-a-penny promotion.

Until, say, World War II, the various entertainment disciplines had remained largely separate: Movie studios made movies, record companies made records, and few people had even seen television. It was Lew Wasserman who led the process of breaking down the barriers, leading the push toward conglomeration from his position as head of the Music Corporation of America, which began as an agency for musicians. Wasserman joined MCA on Dec. 12, 1936, doing publicity for bands. Soon he was out in Hollywood, building the agency's fledgling movie-representation business. Ten years to the day after he joined the agency, Wasserman became its president. In 1952 he went to Screen Actors Guild president (and MCA client) Ronald Reagan and won an exemption from SAG rules that barred agencies from producing. MCA promptly began producing shows for TV. Six years later, Wasserman added to MCA's portfolio by buying Universal Pictures' back lot; in 1962 he announced plans to acquire Universal itself, along with its parent, Decca Records. It was then that MCA got a new nickname--the Octopus--and the feds started to take notice. Facing antitrust proceedings, Wasserman ultimately agreed to sell the agency business and to refrain from further acquisitions for the next seven years. In return he was allowed to acquire Universal and Decca. The company that resulted, with its TV, film, theme-park, and recorded-music divisions, is the model for the modern media conglomerate.

Now, at century's end, conglomeration has made it possible for an idea to travel the world in a heartbeat--to light up thousands of movie screens, to play through millions of headsets, to flicker on a billion TVs. True, that idea sometimes looks like Adam Sandler peeing on a wall. But then, all progress has its price.

This is the ninth in a series of features nominating finalists for our BUSINESSMAN OF THE CENTURY award. We will announce the winner in the Nov. 22 issue of FORTUNE. Stay tuned.