James Montgomery Flagg (my Grandfather) created the original Uncle Sam "I Want You". Although most researches will refer to JMF as the model of his original Uncle Sam, nothing could be farther from the truth. My Mother tried her adult life to correct this error, and I will carry on this monumental task.
In 1916, JMF reluctantly accepted a 4th of July project by Leslie Magazine, and eventually found his Uncle Sam one rainy night on a train bound for Parris Island, where he was to unveil a portrait of the Commandant.
His "symbol of our country" was a young, roughly 17 year old, Marine, which he considered the finest branch of our armed forces. He was able to acquire a 24 hour pass for this "boot" not normally allowed off base, and he aged his model's adolescent face by forty years and turned a circus clown's costume into symbolic dignity (as told to me and written by his daughter, my mother, Faith).
This cover was eventually made into a recruiting poster, at the request of the State Dept, and is now recognized as the most famous war poster of our time.
By WWII, JMF had ironically begun to look remarkably like his original Uncle Sam, and he did indeed use his mirror image in several new posters. When FDR is quoted as saying "saving model hire" in a personal letter to JMF, he is referring to the 2nd World War posters.
Faith would say, "I thought you might find the facts more fun than the fantasies."