Flags have been often times used as rallying points at some point of battles; squaddies would collect around their hues for morale

https://louisarou189.vantagequill.com/posts/the-art-of-flag-making-crafting-authentic-civil-war-flags-for-reenactments

Flags had been at times used as rallying features in the course of battles; squaddies would accumulate around their colorings for morale give a boost to when confronted with overwhelming odds.