On this day in 1862 President Abraham Lincoln signed into law a measure calling for the awarding of a U.S. Army Medal of Honor. In the name of Congress "to such noncommissioned officers and privates as shall most distinguish themselves by their gallantry in action, and other soldier-like qualities during the present insurrection. The previous December, President Lincoln approved a provision creating a U.S. Navy Medal of Valor. 
In 1863 the Medal of Honor was made a permanent military decoration made available to all members, including commissioned officers of the U.S. military. The most medals awarded was during the Civil War and at the end of the conflict the requirements for awarding the medal were standardized and governed by a board of senior military officers.
With only some minor changes the actual Medal of Honor for each branch has changed little from the original design. Since the Civil War some 3,400 men and one woman have been awarded the Medal for heroic actions in U.S. Military conflict.