Al-Ubulla

[5] Toward the end of the Sasanian period, it typically formed part of the territories of the Empire's al-Hira-based Lakhmid vassals.

[1] During the early Muslim conquests in the 630s, al-Ubulla was conquered by the Arab forces of Utba ibn Ghazwan al-Mazini after the defeat of its 500-man Sasanian garrison.

[7][8] In a letter attributed to Utba, he describes the city as the "port of al-Bahrayn (eastern Arabia), Uman, al-Hind (India) and al-Sin (China)".

[5] Following the foundation of the Arab garrison town of Basra further inland, al-Ubulla declined in strategic importance but remained a major trade port until the Mongol invasion.

[5] Yaqut al-Hamawi praised the city and Ibn Hawqal describes the border lands of the Nahr al-Ubulla as a single extensive garden.