What caused the split was Muhammad's death in 632.
Muhammad was not the founder of any branches of Islam. In fact, he was not even the founder of Islam, rather the messenger. As well as this, Muhammad and Islam discourage branches within Islam so it clashes with the question.
Acoording the Quran and speeches of prophet, Shia Muslims believe that just as a prophet is appointed by God alone, only God has the prerogative to appoint the successor to his prophet. They believe God chose Ali to be Muhammad's successor, infallible, the first caliph (khalifa, head of state) of Islam. Muhammad, before his death, designated Ali as his successor. Ali was Muhammad's first cousin and closest living male relative as well as his son-in-law, having married Muhammad's daughter Fatimah.
the disputes between these two sects mainly cuased from different views about authority particularly who is the successor of the prophet and also from teaching of islam religion.
Muhamad didn't name a successor and a schism between Sunni and Shia born. The Shia claimed the right of Ali, the son-in-law of the Prophet Muhammad, and his descendants to lead the Islamic community. Sunnis assert that even though Muhammad never appointed a successor, Abu Bakr was elected first caliph by the Muslim community.
The death of the Prophet Muhammad. It was then decided that as a religious and community leader he should be succeeded, and such a religious successor was called a Caliph; the region and community he ruled over, a Caliphate. This immediately led to the first schism, namely between Shi'ite and Sunni Muslims. The Sunni Muslims considered Muhammad's father-in-law the rightful successor and first Caliph, the Shia Muslims considered his son-in-law the rightful successor.
The division between Sunni and Shiite Muslims originated from a disagreement over who should succeed the Prophet Muhammad as the leader of the Muslim community. Sunnis believed that leadership should follow community consensus, leading to the election of Abu Bakr as the first caliph, while Shiites believed that leadership should stay within the Prophet's family, leading to the belief in Ali, Muhammad's cousin and son-in-law, as his rightful successor. This difference in opinion resulted in a lasting schism in Islam.
According to Peano's axioms, in either system, it is the successor to the successor to the successor to the successor to the successor to 0.
Both Sunni and Shia originate from the Prophet- but then disagree on the succession of Caliphs after his death. One believes that the succession was through his daughter, the other through his brother.
The division between Sunni and Shia Islam emerged after the death of the Prophet Muhammad in 632 CE, primarily over the issue of leadership. Sunnis believed that the community should choose the leader (Caliph), supporting Abu Bakr, a close companion of Muhammad. In contrast, Shia Muslims believed that leadership should remain within Muhammad's family, specifically designating Ali, his cousin and son-in-law, as the rightful successor. This disagreement over succession and authority laid the foundation for the enduring split between the two sects.
There is no war between them Only the extremists create problem
The Umma or the People. According to the Sunnis he was to be chosen democraticly as per the Prophet Muhammeds orders. According to Shiite belief it should be according to blood relation with the Prophet. This is still one of the main reasons for the division between the two sects.