James Cagney: He is that Yankee Doodle Boy!

Yankee Doodle Dandy was released in 1942, and became a smash, 

Warner Brothers biggest success up to that time.

James Cagney was superbly cast as George M. Cohan;

his style of half-singing, half-speaking songs

was evidently very similar to Cohan's style,

as well as his physique and dance moves.

 "H-A-Double R-I..." etc.,

Joan Leslie (dubbed by Sally Sweetland) and Jimmy

put over a new song for producer Sam Harris,

played by Richard Whorf.

 

 Cagney, Jeanne Cagney (Jimmy's real life sister, playing his sister!),

Rosemary DeCamp (11 years younger than Cagney, but playing his mom!),

and Walter Huston...

The Four Cohans.
"My mother thanks you, my father thanks you, my sister thanks you,

and I thank you."

 George M. Cohan supposedly consulted on the film,

coming to several rehearsals and placed his stamp of approval

on Cagney's portrayal of him.

Unfortunately he passed away before the film's release.

Cagney...a song and dance man at heart.