Uncle Sam

He's known as a very popular personification of the us government, expression of patriotic emotion and its usage during the war of 1812. Today when used publicly, creates controversies. The first reference to the real uncle Sam is found in the allegorical book "The Adventures of Uncle Sam in search for his lost honor" by Frederick Augustus Fidfaddy. 

The have been many theories about his possible origins, but the one which is best known comes from the assumption traces the origins of uncle Sam to Sam Wilson from Troy, New York

The image of Uncle Sam appeared on various types of products, starting with cereal and ending with car insurance. He has been present on political and military cartoons. In general, he is widespread everywhere. 

In the beginnings he was depicted together with Columbia whose name comes from Christopher Columb. That is because of the tendency inherited by the people of Renaissance to use allegorical personas to depict some value national, ideological or whatever it might be. 

Uncle Sam was charismatic, his eyebrows, pointed finger and serious pose inspired and made a great impression on people. In fact the government in 1917 and 1918 produced 4 million posters of him and the image was reused in WWII. If we had to compare it to our times we could say that Uncle Sam was one of the earliest memes (or at least meme-like creations)