The Roman War Trumpet was a type of instrument known as a TUBA, which was used in ancient Rome to signal the start and end of battles. It was made of bronze and had a loud, deep sound that could be heard from a great distance. The TUBA was also used to announce important events such as the coronation of a new emperor or the victory of a battle. It was an essential part of Roman warfare and was used to rally troops and intimidate enemies.