The Lost Battalion is the name given to the nine companies of the US 77th Division, roughly 554 men, isolated by German forces during World War I after an American attack in the Argonne Forest in October 1918. Roughly 197 were killed in action and approximately 150 missing or taken prisoner before the 194 remaining men were rescued. They were led by Major Charles W. Whittlesey. On 2 October, the 77th division launched an attack into the Argonne, under the belief that French forces were supporting their left flank and two American units including the 92nd Infantry Division were supporting their right. Within the 77th sector, some units, including Whittlesey's 308th Infantry, were making significant headway. Unknown to Whittlesey's unit, the units to their left and right had been stalled. Without this knowledge, the units that would become known as the Lost Battalion moved beyond the rest of the Allied line and found themselves surrounded by German forces. For the next six days, suffering heavy losses, the men of the Lost Battalion and the American units desperate to relieve them would fight an intense battle in the Argonne Forest.

The 77th Sustainment Brigade is a unit of the United States Army that inherited the lineage of the 77th Infantry Division, which served in World War I and World War II. Its headquarters has been at Fort Dix, New Jersey, since its predecessor command, the 77th Regional Readiness Command, was disestablished in 2008 from Fort Totten in Bayside, Queens, New York. Soldiers from the 77th have served in most major conflicts and contingency operations involving the US since World War II.