Because of some floods some parts of Ka'bah was destroyed. The tribes repaired the walls and it was time to install the Hazarul-Aswad in its place. Each tribe wanted to acquire this honor so a war was near to take place until Abu Umayyah the oldest man in the Quraish tribe suggested that we should let the first man who enters the Masjidul-Haraam decide what to do in this regard. Muhammad s.a.w.a was that man and he was known for his honesty and authenticity among the people of that time.
He prescribed to bring a cloth and put the Hajarul-Aswad inside it and all tribes take one corner of the cloth and at last he himself put the stone in its due place.
So no war took place because of his wise decision.