Uniform buttons served two roles, functional and decorative. They can be found on the sides of service caps, on coats and overcoats, on cuffs, on pocket flaps, on shoulder loops (often called epaulettes), and on Navy shoulder marks. Each service had its distinctive buttons. The United States Army has worn a button bearing an eagle in some form continuously since about 1808. The modern style button featuring the Arms of the United States was introduced in 1902. The earliest Navy button having both an eagle and foul anchor dates from 1797. In 1852 regulations stated that the anchor should be nearly horizontal. On May 14, 1941 the Navy ordered that the head of the eagle face its right side. Buttons made prior to that date generally face left. This was done so that the button would be in accordance with the rules of heraldry, right being the side of honor. The design of the Marine Corps button was introduced in 1821 and has changed very little from that date. The sizes of buttons were specified using an English standard called a line, which is a 40th of an inch. The backs of most buttons have a backmark indicating the manufacturer. Some buttons were sewn on uniforms and others were attached with metal clips that allowed them to be removed when the uniform was cleaned.
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| General Service Button (Brass) | General Service Button (Plastic) | Engineer Officer's Button | Women's Auxillary Army Corps (Plastic) |
All personnel, except for officers of the Corps of Engineers, used the General Service Button. Engineers retained a traditional button that was first used prior to 1814 and bears the motto "Essayons." The motto "Essayons" means "Let us try" in French. Buttons were also made of plastic to conserve brass, which was a vital war material. Buttons came in 45-line (1 1/8-inch) 36-line (9/32-inch) and 25-line 5/8-inch sizes.
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| Navy Officers and Chief Petty Officers (Brass) | Navy Officers and Chief Petty Officers (Plastic) | Navy Officers and Chief Petty Officers (Aviation) |
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| Seamen Short (Pea) Overcoat Button (Plastic) | Seamen Jumper and Trouser Button (Plastic) | Officers Stewards and Cooks Button (1) |
During World War Two Officers and Chief Petty Officers wore the same gilt brass button, which came in four sizes 40-line (one inch), 35-line (7/8-inch), 28-line (7/10-inch) and 22 1/2-line (9/16-inch). Black plastic buttons were worn on the gray working uniform (introduced in 1943) and buttons with a dull antique brown enamel finish were worn the aviation green uniform. With the exception of Chief Petty Officers enlisted men did not wear brass buttons. A special white button bearing an anchor was worn by Officers Stewards and Cooks.
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| Marine Button (Gilt) | Marine Button (Bronze) | Marine Button (Plastic) |
Buttons for Marine officers came in 45-line (1 1/8-inch), 40-line (7/8-inch), 27-line (27/40-inch) and 22-line (22/40-inch) sizes and were in higher relief than those of enlisted men, which came in 45-line (1 1/8-inch), 35-line (3/4 inch) and 25-line (5/8 inch). Gilt buttons were used on dress uniforms and bronze buttons on service uniforms. Plastic buttons were introduced to save on vital war material.
