This song is derived from tunes that British officers made up to make fun of colonial militia in the French and Indian Wars 1765. This continued in the Revolutionary War from 1775 and on. Yankee is an old term derisive from the Dutch nickname 'Janke' and was used to refer to Dutch colonials, but began to refer to any colonial in New England and at times specifically someone from Connecticut. Other foreigners used the term just to refer to an American, often in the short form 'Yank'. Now it means someone from New England. A 'doodle' was fool or simpleton. However, during the Revolutionary War American colonials reversed the song to mock the English. Lyrics for the earliest known version are:

Father and I went down to camp
Along with Captain Gooding
And there we saw the men and boys
As thick as hasty pudding.
Chorus
Yankee doodle, keep it up
Yankee doodle dandy
Mind the music and the step
And with the girls be handy.

There was Captain Washington
Upon a slapping stallion
A-giving orders to his men
I guess there was a million.
Chorus

And then the feathers on his hat
They looked so' tarnal fin-a
I wanted pockily to get
To give to my Jemima.
Chorus

And then we saw a swamping gun
Large as a log of maple
Upon a deuced little cart
A load for father's cattle.
 

Lyrics: Current version

Yankee Doodle went to town
A-riding on a pony
Stuck a feather in his hat
And called it macaroni.

Yankee Doodle, keep it up
Yankee Doodle dandy
Mind the music and the step
And with the girls be handy.

Father and I went down to camp
Along with Captain Gooding
And there we saw the men and boys
As thick as hasty pudding.

Yankee Doodle, keep it up
Yankee Doodle dandy
Mind the music and the step
And with the girls be handy

There was Captain Washington
Upon a slapping stallion
A-giving orders to his men
I guess there was a million.

Yankee Doodle, keep it up
Yankee Doodle dandy
Mind the music and the step
And with the girls be handy.

In 1942 James Cagney  brought  "Yankee Doodle" back for the WWII with the musical "Yankee Doodle Dandy" and the song has appeared in various commercials and films since.