Where Broadway Was Reinvented

The musical Oklahoma!, which opened on Broadway on March 31, 1943, fundamentally changed the American musical theater. Before Oklahoma!, Broadway musicals were revue-style entertainments where songs were inserted for spectacle and had little to do with the story. Rodgers and Hammerstein built their songs, dances, and even the dream ballet directly into the narrative of the show, creating the first integrated musical. The original production ran for 2,212 performances, a record at the time, and its cast album became the first original cast recording to sell over a million copies.

Source: Wikipedia