General service buttons were first introduced in 1854 and replaced branch specific buttons for enlisted men. The button used during
the Civil War had a shield that was flush with the surface. About 1875 this button was replaced with one that had an elevated
shield similar to the one pictured. A specification issued in 1885 clearly shows the later type button. In 1902 these
buttons were replaced by a more modern type button similar to those in use today. Also indicative is the backmark. The firm of Horstmann is one of the oldest and best known of the military outfitters. The book American Military Button Makers and Dealers: Their Backmarks and Dates does not picture this particular backmark. It is similiar to others from the late 19th-Century.
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