Cohan, playing the title character, sings this song as his friend is about to sail to America, looking for evidence aboard ship that will clear his name for allegedly throwing the English Derby. He is sure he'll become a star at Broadway, therefore signing off with: "Give my regards to Broadway." 
The sentimental song has been recorded many times. It was featured prominently in a solo song-and-dance sequence done by James Cagney in his Oscar-winning performance in the 1942 film about Cohan's life, Yankee Doodle Dandy. It was also performed by Al Jolson.
In 1999, National Public Radio included this song in the "NPR 100," in which NPR's music editors sought to compile the one hundred most important American musical works of the 20th century.
The song was included in the 1968 musical George M!, which was based on Cohan's life. Tony Award-winning actor Joel Grey played Cohan in the original Broadway cast and performed the song for the soundtrack.
One of its earliest recordings was by Billy Murray. His recording's short instrumental interludes contain the two closing lines of the chorus to The Yankee Doodle Boy, which was the other famous song from Little Johnny Jones: