It is the great watershed event. All other musicals either came before it or followed it. It is such a fact of life in the American Theater that its importance cannot be taken for granted. Maybe there are greater musicals. Certainly there are more daring ones. The form itself has grown more sophisticated in the last half century. But what happened on the night of March 31, 1943, on the stage of Broadway’s St. James Theatre, changed forever the way American musical theater would sound, look, and communicate. It was a revolution. A revolution dressed up in amiable down-home humor, irresistible songs, fluid and balletic dancing, and – in the grimmest days of World War II – a vibrant, all-American sense of hope

What seemed like magic, though, had been – just weeks before – a not terribly promising show called Away We Go! (because no one could think of a better title) put together by a group of people who were badly in need of a Broadway hit.

Composer Richard Rogers and lyricist-librettist Oscar Hammerstein II were teaming up for the first time, at a point of mutual need: Rodgers long collaboration with the troubled lyricist Lorenz Hart was coming to a bitter and tragic end, and Hammerstein hadn’t been associated with a hit in a decade. The choreographer Agnes de Mille was a Broadway novice, and the director Rouben Mamoulian wasn’t as comfortable with the form (though he had staged the premiere of Porgy and Bess) as Rodgers and Hammerstein had hoped he’d be. The producing organization, the Theatre Guild, was prestigious. But it, too, had fallen on hard times. The Guild’s directors, Lawrence Langner and Theresa Helburn, had suggested this musical version of Lynn Riggs’ play Green Grow The Lilacs mainly because they controlled the rights to the play and desperately needed an easily assembled hit show to restore The Guild’s fortunes.

In the difficult struggle to raise backing, Helburn hit on the then-novel idea of getting a movie studio to invest in the Broadway production of Oklahoma!, with part of the deal involving the film rights to the new musical.

MGM was the likeliest candidate, since it held the necessary film rights to Riggs’ play. The studio passed on the idea, though Helburn got MGM to agree to sell those rights to the show’s investors within 30 days of the musical’s opening. The upshot of MGM’s decision was that Rodgers, Hammerstein and the Theatre Guild were able to exercise that option and snap up the studio’s film rights to Green Grow the Lilacs – which as Rodgers wrote, they did within 30 hours of Oklahoma! Opening – in order to own, free and clear, one of the richest potential film properties since Gone with the Wind.

Back in 1942, Rodgers, a Connecticut neighbor of the Theatre Guild’s Langner and Helburn, was approached about writing a musical version of Green Grow the Lilacs at a time when he began to see his working relationship collapse with the tragic, chronically alcoholic Hart. Rodgers saw a musical in the material. Hammerstein was available and he was excited about the project, too. But Rodgers and Hart agreed to part for this project, with Hart – drowning in his own problems, but no doubt hurt by Rodgers determination – telling his partner that he thought a musical version of Green Grow the Lilacs was a mistake.

From the start, Rodgers and Hammerstein couldn’t have been luckier with each other.

Both were industrious hard workers, methodical about their craft, and they were rich in experience when they began working together. There was no need for questions. They just started writing the show, usually with Hammerstein supplying the lyrics first. Rodgers respected his new partner’s understanding of form and, after years of struggling with the brilliant but undependable Hart, he loved Hammerstein’s quiet assurance and his ability to deliver extraordinary work on time.

Not that getting Oklahoma! on its feet was easy, though. With an unknown cast – Alfred Drake, Joan Roberts and Celeste Holm would all be overnight sensations on April 1 – and very little enthusiasm from the theater community, the show couldn’t stir up any excitement, much less money. Backers' auditions yielded little support, and it was a hearty band of true believers who took the big risk on this unusual project.

So strong was the response in New Haven tryouts that the original title was dropped in favor of Oklahoma!, though it was too late to change the posters for Boston. One song was scrapped ("Boys and Girls Like You and Me") between New Haven and Boston, and the title song became a choral number instead of a solo for Curly. All that was left for the public to discover the show. And it did, it did.

Oklahoma had hit Broadway with an impact unprecedented for a musical. The now common concept of “original cast recording” was born with Oklahoma!, the idea of Jack Kapp of Decca records, one that Rodgers and Hammerstein enthusiastically embraced. In artistic and business terms, the show established new standards for the musical theater, and its instant popularity – with a nation consumed with fighting World War II – went far beyond anyone’s expectations.

Oklahoma closed on May 29, 1948 after a then record-breaking five years and nine weeks run.