Flags had been regularly used as rallying issues right through battles; infantrymen might accumulate around their colors for morale

https://dominickuqhq312.greyhavendaily.com/posts/civil-war-flag-etiquette-understanding-proper-display-and-respect

Flags were on occasion used as rallying elements for the period of battles; squaddies would bring together around their colours for morale reinforce while confronted with overwhelming odds.