Shi'a is the short form of Shi'atul Ali, or Party of Ali, which rejected the first Caliph Abu Bakr in favor of Ali. Shi'a Islam is the less orthodox of the two main branches of Islam and accepts the idea of intercession by dead imams on behalf of the living. Shi'a Islam was once led by the Caliphs of the Fatimid Caliphate, but it later became a minority religion as Sunni Islam became the dominant branch. Today, Shia Islam is the dominant religion in Iran, Azerbaijan, and Iraq, with a large presence in Lebanon, Syria, and Yemen. 89% of Iranians, 85% of Azerbaijanis, 75% of Iraqis, 47% of Yemenis, 27% of Lebanese, and 13% of Syrians are Shi'ites, with minorities in the other Muslim countries and the non-Muslim world.