The Lost Battalion is a 1919 American silent war film about units of the 77th Infantry Division (the "Lost Battalion") penetrating deep into the Argonne Forest of France during World War I.

The men of the 308th Infantry Regiment, part of Major General Robert Alexander's 77th Infantry Division, have been drafted from diverse ethnic, economic, and social groups in New York City.

Two men are fighting Chinatown tongs, one is a burglar, another is a wealthy merchant's son in love with his father's stenographer, who dreams of becoming the greatest movie actress, another is a private in love with the merchant's ward, and finally there is "the Kicker," who finds fault with everything.

After training in Yaphank and in France, the 463 men advance under the command of Lieutenant Colonel Charles W. Whittlesey into the "Pocket" of the Argonne Forest, to help break down the supposedly impregnable German defense.

The Chinese rivals fight bravely side-by-side, while the burglar dies heroically.