In the Islamic era, the Postal System was established by ________?

In the Islamic era, the Postal System was established by ________?

اسلامی دور میں ڈاک کا نظام کس نے متعارف کروایا تھا؟
Explanation
Ameer Muawiyah (R.A) established Postal System
Purposes: speed up the arrival of intelligence from his outlying provinces.
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About  Ameer Muawiyah (R.A)
Mu'awiya I  was the founder and first caliph of the Umayyad Caliphate serving from 661 until his death.
 He became caliph less than thirty years after the death of the Islamic prophet Muhammadﷺ
Muawiyah was appointed as the Governor of Syria after his brother Yazid ibn Abu Sufyan died