tribes, especially in ancient civilizations, are important for families and neighbors to grow close, and for communities to protect each other. But their are downsides to this idea of the tribe. tribes are not very connected with other tribes, they have not alot of skills for working with each other. they all have different customs, different beliefs, and different opinions.  because of this, when islam brings these tribes together, they can't communicate because of their differences. Also many lower tribes were looked down upon by higher ones, and this went against Muhammad's teachings. when Muhammad's power needed to be passed on, these different opinions flared up, and fights broke out. Muslims broke up into the Sunnis and the Shiites, who still fight today. The Sunnis believe that the power should go to whoever was taught by Muhammad, and the Shiites think that the power should go through his bloodline. This idea also relates back to one of the tribes traditions which is that many small fights will elevate and last for generations. In conclusion, because of tribes and the concept of the tribe in islamic history, the muslim people are broken in two.