The symbolism employed in the United States First Army shoulder sleeve insignia is straightforward. Red and white are the colors of distinguishing flags for armies (a fact that loses its import on OCP and UCP subdued patches) and "A" is is used to signify a field army on military charts.
August 10, 2018 marked the 100th anniversary of the organization of First Army, which was redesignated First United States Army in 1957 and then reverted to its original designation of First Army in 2006. It was the first of three U.S. field armies deployed during World War I, and took part in three campaigns during the brief period of combat it saw.
In the Second World War, five of its divisions took part in the D-Day landings and airdrops, with three divisions going ashore and Omaha and Utah beaches and two Airborne divisions being dropped behind German lines. In 1945, it was First Army units that secured the bridge at Remagen before the Germans could demolish it, allowed U.S. forces to secure a beachhead inside Germany and eliminating any chance of a German counterstroke to hold back the Allies.
In the decades following World War II, First Army’s mission has revolved around training of both active and reserve (USAR and ARNG) troops and civilian assistance missions. In 2006, it was tasked with training and support missions formerly carried out by United States Fifth Army.