Why was the song “Swanee” important to George Gershwin’s career?

The song “Swanee” was a pivotal turning point in George Gershwin’s career because it transformed him into an overnight celebrity.1

When the famous entertainer Al Jolson performed the song in the 1919 musical Sinbad, it became a massive commercial success. The song’s popularity resulted in the sale of more than two million recordings and one million copies of sheet music, effectively launching Gershwin’s professional reputation and establishing his status as a major composer.1