Islam is divided into two major sects, Sunni and Shia Islam, each with its own sub-sects. Large numbers of Shia Arab Muslims live in some Arab countries including Lebanon, Yemen, Bahrain, Iraq, Saudi Arabia, Kuwait, Oman, the UAE, and Qatar.
Shia Muslims are a numerical majority in Iraq and Bahrain. Approximately 35% of the population in Yemen and half of the Muslims in Lebanon are Shia Muslims. There is also a very large population of Shia Muslims living in the Persian Gulf countries especially in Saudi Arabia. An estimated 5–10%[1][2] of citizens in Saudi Arabia are Shia Muslims, most of whom are adherents to Twelver Shia Islam. Twelvers are predominantly represented by the Baharna community living in the Eastern Province, with the largest concentrations in Qatif, and half the population in al-Hasa. In addition there is a small Twelver Shia minority in Medina (called the Nakhawila). Sizable and Isma'ili communities also live in Najran along the border with Yemen. Saudi Arabia officially follows Wahhabism, a strict, recently established sect of Sunni Islam. There is little freedom of religion between the different sects even whilst all of the population are Muslims. Smaller Shia groups are present in Egypt and Jordan.
Despite the heavy presence of Shia Muslims in some Arab countries, particularly among the population of the Persian Gulf Arab countries, they have been treated poorly throughout history.[3] For both historical and political reasons, Shi'a Arabs have fared relative poorly in much of the Arab world, and the topic of Shi‘ism and Shia groups is one of the most sensitive issues for the Sunni elite.[4]