Timeline of the history of Islam (9th century)

== 9th century (801–900 CE / 184–288 AH) == 801: Death of Rābiʿa al-ʿAdawiyya al-Qaysiyya famous Arab Muslim saint and Sufi mystic. 802: The Mecca Protocol: Caliph Harun al-Rashid and the leading officials of the Abbasid Caliphate perform the hajj to Mecca, where the line of succession is finalized.

Source: Wikipedia — Timeline of the history of Islam (9th century) (CC BY-SA 4.0)