To be sure, Hart had reasons beyond a desire to just drink. Rodgers and Hart had never written a musical with a Western setting. Most of their shows had been set either in semimythical places, like ancient Greece, or in great cities. Indeed, the most Western song they had ever written was probably “Way Out West on West End Avenue,” from Babes in Arms .

By pure coincidence, Hammerstein also had sensed the musical in Green Grow the Lilacs , in early 1942. He went to California and tried to interest Jerome Kern, then living in Beverly Hills, but Kern just didn’t see it. Returning East, Hammerstein nonetheless asked the Theatre Guild for the rights. He was told that Rodgers and Hart had already been given them, but that they needed someone to write the book. Hammerstein jumped at it.

On July 23, 1943, there appeared a notice in The New York Times that the trio would begin work shortly, Rodgers on music, Hart on lyrics, and Hammerstein on the book.

But the more Hart thought about it, the less he wanted anything to do with it. He wanted to go off to Mexico. He didn’t want to think about doing another show. And he certainly didn’t want to make a musical of Green Grow the Lilacs .

Rodgers, perhaps sensing with the instincts of genius a golden opportunity, was determined. He warned Hart that the show meant a lot to him. If Hart refused, he said, he would have to look for another collaborator to write the lyrics.

“Anyone in mind?” Hart asked.

“Yes, Oscar Hammerstein.”

“Well,” said Hart, who had destroyed only himself, not the feel for theater that made him great, “you couldn’t pick a better man.” Rodgers and Hart had become Rodgers and Hart and Hammerstein had become Rodgers and Hammerstein.

Hammerstein was as different from Hart as two great lyricists could possibly be. Hart’s lyrics were intricate, witty, bittersweet. His talent for rhyming was surpassed by no one and equaled, perhaps, only by W. S. Gilbert and, later, Stephen Sondheim. Hammerstein’s lyrics were carefully wrought and deceptively simple, more concerned with character than with being clever. Hammerstein could never have written the words to “Bewitched, Bothered, and Bewildered” or “Glad to Be Unhappy.” But equally Hart could never have written “Ol’ Man River” or “If I Loved You.”

They changed the rules by writing the lyrics before the tunes and ignoring old conventions about stage action.

There were great personal differences as well. Hammerstein was large, over six foot two. He was at peace with himself. He rose early and drank little. He was a careful and very hard worker. The methodical Rodgers, after years of having to pry his lyricist out of gin mills and steam rooms to get a song written, found Hammerstein’s work habits a great relief, and the two hit it off as collaborators from the start.

As they set to work on turning Green Grow the Lilacs into a musical, they made two decisions almost immediately that had a deep impact on Oklahoma! The first was that Hammerstein would write the lyrics and Rodgers would then set them to music.

Hart had always needed a tune to provoke the lyrics out of him. Indeed, writing the music first had long been the usual, and peculiar, Broadway custom. It stemmed, perhaps, from the fact that many early Broadway composers had been European, with limited command of English and its stress patterns.

By reversing the procedure, Hammerstein had a much freer hand to find the exact right words for the character and the situation. The effect of this way of writing songs on Rodgers’s music was marked, and the music of Rodgers and Hammerstein would sound very different from that of Rodgers and Hart, while still always sounding ineluctably of Richard Rodgers.

The second decision was to let the dramatic situation, not Broadway musical conventions, dictate what happened onstage. For instance, convention said that it was important to get the chorus line on view as soon as possible, preferably for the opening number. But it would be nearly forty minutes before the chorus of Oklahoma! appeared onstage. (This, of course, was the origin of Mike Todd’s “no legs” complaint.)