The Shia branch of Yemen, which holds that any qualified descendant of the Prophet who rises for the office may be Imam, and stands closest of the Shia branches to Sunni practice.
Zaidi Shi'ism takes its name from Zayd ibn Ali, whose rising in 740 set its pattern: the Imam is not designated by birth alone but must claim the office and be learned and capable. It governed northern Yemen for a thousand years.
Sources
Primary
- The Musnad of Zayd ibn Ali.
Secondary
- Cornelis van Arendonk and the Zaydi manuscript tradition surveys.