Medal of Honor Day is observed in the United States every March 25 to honor recipients of the Medal of Honor, the country's highest personal military decoration. This observance highlights the courage and heroism of military personnel who have distinguished themselves by acts of valor. The day commemorates the anniversary of the first Medals of Honor awarded to six raiders from the Great Locomotive Chase during the Civil War on March 25, 1863. The Medal of Honor was established following suggestions from Iowa senator James W. Grimes and Massachusetts senator Henry Wilson, with President Abraham Lincoln signing it into law in 1861. The medal is awarded by the President and can be nominated through a service member's chain of command or by a member of Congress. Since 1941, many Medals of Honor have been awarded posthumously, reflecting the significant sacrifices made by military personnel.