Hamilton "Ham" Coolidge (1895-1918) was one of many young men from wealthy New England families who enlisted during World War I. The collection contains materials related to Captain Coolidge's service a pilot with the U.S. Army Air Service 94th Aero Squadron. Coolidge achieved Ace status, was awarded the Distinguished Service Cross, and was killed in action.

The collection contains a photograph album from the World War I career of Herman J. Sommerhauser (1895-1949), who may have served with the U.S. Army Air Service, 650th Aero Squadron in France.