Flags had been in many instances used as rallying elements for the period of battles; infantrymen could collect round their colors for morale

https://zionzikt868.silverstonebrief.com/posts/reenactors-and-their-favorite-civil-war-flags-a-community-perspective-2

Flags have been typically used as rallying elements for the time of battles; infantrymen might collect round their hues for morale strengthen when faced with overwhelming odds.