The subculture of flying flags dates to come back centuries, serving as a means of verbal exchange on battlefields

https://spark-wiki.win/index.php/The_Art_of_Flag_Flying:_Tips_for_Displaying_Flags_with_Respect_and_Honor

The tradition of flying flags dates back centuries, serving as a means of verbal exchange on battlefields. They conveyed messages of allegiance and victory, enabling armies to coordinate events and solutions without verbal verbal exchange.