The umayyad dynasty established as the official language of the caliphate. arabic. hebrew. cyrillic. sanskrit.

Arabic.

Explanation:

The Umayyad dynasty was the ruling power of the Islamic Caliphate in 661 to 750 AD. The Umayyad Caliphat was one of the four major caliphates that were established after Muhammad died.

The Umayyads carry on the Muslim conquests of Central Asia, the Arabian peninsula and other regions, thus making it one of the largest empires in the history of the world. They established the use of Arabic as the official language of the caliphate. Though predominantly a Muslim kingdom, they ruled over even diverse religions like Christianity and Jewish. There was no trouble even with the diverse religions all living under a Muslim ruler.