Uncle Sam is a personification of the United States. Uncle Sam, a name with the same initials as United States, is generally depicted as a tall, thin man with a long white beard wearing a top hat and a suit of red white and blue. Samuel Wilson was officially recognized by the United States Congress in 1961 as the source for the mythical Uncle Sam. Wilson supplied the army with barrels of beef during the War of 1812. The barrels were stamped with “U.S.” to signify that they were owned by the U.S. government, the soldiers comically attributed the initials to “Uncle Sam” Wilson, the supplier of the beef. Newspapers of the time adopted the moniker Uncle Sam to refer to the federal government. The image that we associate with Uncle Sam today was developed by Thomas Nast, a political cartoonist, in the 1860s and 1870s. Both Uncle and Sam are capitalized, as together they constitute a proper name.
Examples
But where a war of words once played out in the pages of Russia’s Pravda, Uncle Sam recruiting posters, or on the radio, it now increasingly rages online. (The Christian Science Monitor)
The Kansas Museum of History’s Special exhibit What’s Cooking, Uncle Sam? explains our food supply from the farm to the dinner table and explores the records of the National Archives that trace the Government’s effect on what Americans eat. (The Topeka Capital-Journal)
Better than any report on the federal government’s “critical skills gap,” the cybertheft of 22 million federal personnel records demonstrates Uncle Sam’s need for cyber experts. (The Washington Post)
In the early 50s Manto wrote a number of essays entitled “Letters to Uncle Sam” which are distressingly prophetic on the direction that Pakistan was to take. (The Guardian)