Muslim Arakanese or Rohingya are indigenous to Arakan. Having genealogical linkup with the people of Wesali or Vesali kingdom of Arakan, the Rohingya of today are a perfect example of its ancient inhabitants.
The early people in Arakan were descended from Aryans. They were Indians resembling the people of Bengal. “The area now known as North Arakan had been for many years before the 8th century the seat of Hindu dynasties.
In 788 A.D. a new dynasty, known as the Chandras, founded the city of Wesali; this city became a noted trade port to which as many as a thousand ships came annually;… their territory extended as far north as Chittagong; …Wesali was an easterly Hindu kingdom of Bengal following the Mahayanist form of Buddhism and that both government and people were Indian..”
The Burmese do not seem to have settled in Arakan until possibly as late as the tenth century AD.
The Rakhines were the last significant group to come to Arakan. They appear to have been an advance guard of Burmans who began to cross the Arakan Yoma in ninth century. And they “could not be genealogically the same as to the people of Dannya Waddy and Wethali dynasties.”
In old Burmese the name Rakhine first appeared in slave names in the inscriptions of 12th century.  Dr. S.B. Kanango, said the name Rakhine was given by Burman and it was found in 12th to 15th century stone inscriptions of Tuparon, Sagaing.
In early days not a single inscription was found in present day speaking Rakhine language.
“The scripture of those early days found in Arakan indicate that they were in early Bengali script and thence the culture there also was Bengali.” Hence earlier dynasties are thought to have been Indians, ruling over a population similar to that of Bengal”
But in medieval times there was a reorientation eastward; the area fell under Pagan’s dominance, and Arakanese people began to speak a dialect of Burmese, something that continues to this day. With Burmese influence came ties to Ceylon and the gradual prominence of Theravada Buddhism.
Arabs were the earliest people to travel to the east by sea. They were in contact with Arakan even during the pre-Islamic days. The Arakanese first received the message of Islam from the ship wracked Arabs in 788 A.D. Such ship-wrecks were occurred over and over in the coasts of Arakan and Chittagong.
This Arab presence, with the message of Islam, made up the nucleus of Muslim society in Arakan. Thus in Wesali the Arakanese practiced Hinduism, Mahayanist form of Buddhism and Islam.
The Burmese military regime affirmed in its official book Sasana Ronwas Htunzepho, published in 1997, “Islam spread and deeply rooted in Arakan since 8th century from where it further spread into interior Burma”.
Meanwhile, “the Arab influence increased to such a large extent in Chittagong during mid 10th century AD that a small Muslim kingdom was established in this region, and the ruler of the kingdom was called Sultan. Possibly the area from the east bank of the Meghna River to the Naf was under this Sultan.”
Islam developed slowly but surely in natural way. After the advent of Muslim rule in Bengal in 1203, the Muslim population of Arakan increased. Their number grew fast during the Mrauk-U dynasty. There was large scale conversion of Buddhists to Islam during 15th to 18th centuries.
When the Dutch industrialists were ordered by the king to quit Arakan they were afraid of leaving behind their offspring through local wives for fear of their conversion to Islam.
“It had been reported at Batavia that these children were being brought up as Muslims, and the pious Dutch Calvinists were extremely horrified”
The relations between Arakan and Chittagong were based on historical, geo-political and ethnological considerations.
“The Chittagong region was under the Vesali kingdom of Arakan during the 6th to 8th centuries and under the Mrauk U kingdom of Arakan in the 16th and 17th centuries.” Because of the political, cultural and commercial links between those two territories, Arakan used to be called ‘extended Chittagong’.
The 15th century was a great turning point in the history of Arakan; during this time a large contingent of Muslims entered Arakan from Bengal and they went there by invitation of the ruling princes. The cause was political.
Here the history of Arakan intersects with the history of India and especially with Bengal. An age old intercourse between Bengal and Arakan has left distinctive marks on various aspects of society, culture and administration of both countries.
The Muslims were an integral part in the political entity of Arakan. They were rulers, administrators and kingmakers in Arakan for more than 350 years.
It was Bengal King Sultan Jalal Uddin (1415-1433 AD) of Gaur, a Hindu convert Muslim who helped Rakhine King Narameit Hla with a strong Muslim force to restore him to his throne in Arakan. “Why Muslim army? Because there virtually was no Rakhaing of prime age left to be soldiers”.
So the Muslims were the backbone of the defense “He (Narameikhla) spoke Persian, Hindi, and Bengali on the top of his mother tongue Rakhaing.” 
The Arakanese Kings nurtured sincere admiration towards the Muslim communities. “For this reason they entrusted the chief administrative posts of government department including that of the defense to the Muslims.”
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