In 1950, Gertrude Lawrence's attorney and business manager, Fanny Holtzmann, was worried that Lawrence's star was fading. When she received a copy of Margaret Landon's 1944 book Anna and the King of Siam, she thought that it would make a good vehicle. Lawrence purchased the rights to adapt the book as a play. Holtzmann approached Cole Porter to write the score but he wasn't interested. She was going to approach Lawrence's longtime friend Nöel Coward, but she met Dorothy Hammerstein (Oscar's wife) by chance. She pressed Dorothy to have her husband read the book if she sent it over. Holtzmann also talked to Dorothy Rodgers (Richard's wife).
Coincidentally both wives had read the book when it first came out and had suggested that their husbands musicalize it. However, the two writers weren't interested because the book is episodic and lacks a story. When they saw the 1946 film adaptation (which starred Irene Dunne and Rex Harrison), they were interested.