Al-Mansur

Al-Mansur established a centralized bureaucracy modeled on Sassanid practices, creating the office of the vizier and a postal service (barid). These reforms improved tax collection, communication, and governance across the vast Abbasid Empire.

Al-Mansur sponsored the translation of Greek, Persian, and Indian scientific and philosophical works into Arabic. This initiative laid the foundation for the Abbasid translation movement, which later flourished under the House of Wisdom and preserved classical knowledge.

After the death of his brother As-Saffah, Al-Mansur became the second Abbasid caliph. He systematically eliminated rivals, including the powerful Barmakid family and other potential claimants, to secure his rule and establish the Abbasid dynasty as the sole ruling house.

Al-Mansur faced a major rebellion led by Muhammad al-Nafs al-Zakiyya, a descendant of Ali, who claimed the caliphate. The revolt was crushed by Abbasid forces, and Muhammad was killed, solidifying Abbasid control against Alid claimants.

Al-Mansur ordered the construction of the new capital city, Baghdad, on the west bank of the Tigris River. The city was designed as a circular 'Round City' and became the administrative and cultural center of the Abbasid Caliphate, replacing the previous capital at Al-Hashimiya.