What if it had been Thunderclan that was forced to leave the forest instead of Skyclan?

Firestar most likely never had been heard of, meaning that the "Three" never would have been heard of, meaning that the battle between Starclan, Dark Forest, and the living Clans never would've happened *spoiler alert* Firestar was never beat for FIVE series and was killed por a árvore ! stupid, I always liked Tigerstar anyways