In the 11th century, a turbulent period occurred in the history of Malay Archipelago, the Chola Navy crossed the ocean and attacked the Srivijaya kingdom of Sangrama Vijayatungavarman, Kadaram (Kedah), an important fortified city in the Malayan peninsula was sacked and the king was taken captive. Soon after that, the king of Kedah Phra Ong Mahawangsa became the first ruler to abandon the traditional Hindu faith, and converted to Islam with the Sultanate of Kedah established in year 1136. Samudera Pasai converted to Islam in the year 1267, and many other rulers follow suit. There are several theories to the Islamization process in Southeast Asia. The first theory is trade. The expansion of trade among West Asia, India and Southeast Asia helped the spread of the religion as Muslim traders brought Islam to the region. The second theory is the role of missionaries or Sufis. The Sufi missionaries played a significant role in spreading the faith by syncretising Islamic ideas with existing local beliefs and religious notions. Finally, the ruling classes embraced Islam which further aided the permeation of the religion throughout the region. The ruler of the region's most important port, Malacca Sultanate, embraced Islam in the 15th century, heralding a period of accelerated conversion of Islam throughout the region as the religion provided a unifying force among the ruling and trading classes. ( Đoạn này e k biết có nên để thế này không, vì nó là 2 giả thuyết nên nghe nó cứ k tin cậy).
Islam in Indonesia.
As we know, Islam is the dominant religion in Indonesia, but not many people know that the amount of Muslims in Indonesia is larger than anywhere else in the world, with approximately 202.9 million identified as Muslim (88.2% of the total population) as of 2009. To foreign observers as well as to many Indonesians themselves, Indonesian Islam has always appeared to be very different from Islam at most other