It is important to note that although the Muslim community or Ummah is rather unified due to the rigidity of its five pillars, the Holy Quran and the Prophet Muhammad, two larger communities exist, which are Sunni and Shiite. The former group is the largest one, but they both agree on the core Islamic beliefs. Therefore, the split of the Ummah is a result of historical disagreement among early Muslims after the death of the Prophet Muhammad.
Historically, the Muslim Ummah was unified under Islam with its leader and last Prophet Muhammad. The split took place after his death because Muslims did not agree on the succession of leadership after Muhammad. The group that would form Sunnis believed that the most prominent members of the Ummah should become the successors, while the group that would form Shiites stated that only Muhammad’s family should take on leadership, such as the Prophet’s cousin Ali. Sunnis comprise 85% of 1.6 billion Muslims globally, whereas only 15% belong to Shiites. The most important characteristic between the two groups can be seen in regards to leadership, where Shiites perceive their Imams as sinless and infallibly authoritative. However, Sunnis do not believe that leadership is a birthright, which is why their leaders must earn their positions within the Ummah. The majority of Shiites live in Iran, whereas the most well-known Sunni country is Saudi Arabia.
In conclusion, both Shiites and Sunnis believe in the core Islamic faiths, such as the five pillars of Islam, the Quran, and Hadith. The split originated after the death of Prophet Muhammad, where one side wanted to appoint his family member and the other top Muslims of the Ummah. Therefore, the most significant difference can be found in leadership-centered beliefs. Iran is an example of a Shiite nation, and Saudi Arabia is Sunni.