The 6888th Central Postal Directory Battalion was the only one comprised of Black women to be sent overseas during World War II.

Black female unit, recognized for its vital wartime contributions, sorted a 17 million mail backlog in three months and was recognized for its vital wartime contributions.

On Tuesday, the 6888th Central Postal Directory Battalion — the only mostly Black, all-women unit to serve overseas during World War II — was awarded the Congressional Gold Medal, Congress’ highest civilian honor, at the U.S. Capitol, according to ABC News.