Buyid Dynasty

State · 936–1055 CE · at its largest around 980 CE

A Shia dynasty from Daylam that ruled western Iran and Iraq and took control of Baghdad in 945, keeping the Abbasid caliphs as figureheads. The Seljuks ended its rule.

On its lands while it lasted

Ecbatana (c. 550 BCE – c. 1800 CE): Capital of Achaemenid Empire (550 BCE–330 BCE).
Abbasid Caliphate (750–1258 CE): The Abbasid dynasty, descended from Muhammad's uncle, took the caliphate from the Umayyads and ruled from Iraq, presiding over the Islamic Golden Age.
Isfahan (c. 936 CE): Capital of Ziyarid dynasty (936–979), Great Seljuk Empire (1040–1194).
Hyrcania (c. 936 CE): Capital of Ziyarid dynasty (936–979).
Ray (c. 936 CE): Capital of Ziyarid dynasty (936–979), Great Seljuk Empire (1040–1194).
Avicenna (c. 980 CE – 1037 CE): A Persian physician and philosopher, author of The Canon of Medicine and The Book of Healing, one of the most influential thinkers of the Islamic Golden Age.
The Canon of Medicine (1025 CE): Avicenna's five-volume medical encyclopedia, completed around 1025, became a standard textbook in the Islamic world and in European universities for centuries.
Nishapur (c. 1040 CE): Capital of Great Seljuk Empire (1040–1194).
Hamadan (c. 1040 CE): Capital of Great Seljuk Empire (1040–1194).
Omar Khayyam (1048 CE – 1131 CE): Persian mathematician, astronomer and poet who solved cubic equations geometrically, helped reform the calendar, and is famed for the quatrains of the Rubaiyat.
Seljuks enter Baghdad (1055 CE): The Seljuk leader Tughril Beg entered Baghdad and took control of the Abbasid Caliphate, making the Seljuk Turks the leading power in the Muslim east.