Westchester Congressman George Latimer joined officials and family members in laying a wreath at Arlington National Cemetery on Wednesday.
The group was honoring the Harlem Hellfighters and their descendants.
The Hellfighters were the 369th Infantry Regiment of the New York Army National Guard during both World Wars.
It was known as one of the first African-American regiments to serve in World War I.
22 Harlem Hellfighters were from Mount Vernon.