Final answer:
The Umayyad caliphs ruled through The Umayyad Caliphate, centered in Damascus, spreading Islam across various regions and establishing Arabic as the official language before the Abbasid Caliphate succeeded them.
Step-by-step explanation:
The Umayyad caliphs ruled their empire through The Umayyad Caliphate (B), which was centered in Damascus. The Umayyads established themselves as a proper empire, ruling through institutions and bureaucratic routines. They moved the capital to Damascus, minted their coins, set up a postal service, and made Arabic the official language of the state. Under their reign, the caliphate spread across the Middle East, North Africa, and parts of Europe.
The Umayyads were pivotal in consolidating Muslim rule and extending the frontiers of Islam, establishing administrative structures, and solidifying Arabic as the official language. After the Umayyads, the Abbasid Caliphate rose to power in 750, shifting the capital to Baghdad and marking a new era in Islamic history.