USMC, U.S. ARMY, MILITIA, 1821 PATTERN, EAGLE PLATE FOR DRESS HAT, VINTAGE

3” wing span, the retention wires are missing.

This eagle plate was worn by the USMC and the U.S. Army Militia and actually dates from the 1830’s to 1840’s.

This is very well described on pages 20-21 of United States Marine Corps Emblems, 1804 to World War I by Frederick L. Briuer, PH.D.