A concise official history recounts the expansion, organization, and activities of the Marine Corps during the World War, combining personnel statistics with descriptions of recruiting, training, unit formation, deployments, and departmental administration. It outlines combat operations by Marine brigades and regiments on the Western Front, summaries of major engagements and citations awarded by allied commands, casualty and decoration statistics, and support roles including naval detachments, aviation, and reserve forces. The work also addresses logistical, paymaster, and quartermaster functions, the return and demobilization of forces, and provides tables and footnoted data to document strength, movements, and outcomes.