Zaydis (or, for Westerners, "Fivers") are the nearest to the Sunnis in their theology, and are often referred to as the "fifth madhhab (school)", after the four Sunni orthodox schools of jurisprudence. Named after Zayd bin Ali, grandson of Husayn, and formed by his followers. While most Shias take Muhammed Al-Baqir to be the fifth Imam, Zaydis regard his brother Zayd as Imam. They are particularly prominent in modern Yemen.
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