Zaydi Alid dynasties

State · 866–935 CE · at its largest around 870 CE

Zaydi Shia dynasties of descendants of Ali who established states in Tabaristan and Daylam on Iran's Caspian coast, beginning with Hasan ibn Zayd in 864.

On its lands while it lasted

• Al-Razi (c. 865 CE – 925 CE): A Persian physician and chemist from Rey who wrote influential medical encyclopedias and gave an early clinical description distinguishing smallpox from measles.
• Amol (c. 866 CE): Capital of Zaydi Alid dynasties (866–928), Ziyarid dynasty (936–979).

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