Today is National Navajo Code Talkers Day. Four surviving code talkers were honored in the Navajo Nation's capital. | U.S. Marine Corps

The Code Talkers used native languages to send military messages before World War II. Choctaw, for example, was successfully used during World War I. But the Marine Corps needed an “unbreakable” code for its island-hopping campaign in the Pacific. Navajo, which was unwritten and known by few outside the tribe, seemed to fit the Corps’ requirements. Twenty-nine Navajos were recruited to develop the code in 1942. They took their language and developed a “Type One Code” that assigned a Navajo word

During #WWII, Navajo code talkers used their unique, unbreakable language to protect American military communications -- a talent that was especially helpful during the Battle of #IwoJima and throughout the Pacific. On National Navajo Code Talker Day, we honor members of the Navajo Nation and all Native Americans whose vital roles in the war saved countless lives. #HonorThem #KnowYourMil | U.S. Department of War