The tradition of flying flags dates returned centuries, serving as a means of conversation on battlefields

https://dantejpgy787.evercolumn.com/posts/flying-the-american-flag-a-tribute-to-honor-and-heritage

The custom of flying flags dates back centuries, serving as a way of communique on battlefields. They conveyed messages of allegiance and victory, permitting armies to coordinate actions and tactics with no verbal communication.