The US nickname Uncle Sam was derived from Uncle Sam Wilson, a meat packer in Troy, New York. According to Isaac Asimov’s Book of Facts, Sam Wilson stamped the letters “US” on meat barrels he prepared for the US Army during the War of 1812. Some workmen interpreted the US for “Uncle Sam” and so the legend grew.
The Uncle Sam figure took on the image of Abraham Lincoln in newspaper cartoons during the American Civil War.
Uncle Sam is the personification of the United States government. The original Uncle Sam poster was designed by James Montgomery Flagg in 1916, using his own face. The design was based on the Lord Kitchener poster of three years earlier which also called men to arms.
The Uncle Sam poster is considered to be the world’s most famous poster.