From Empire of the Winds: The Global Role of Asia’s Great Archipelago, by Philip Bowring (I.B. Tauris, 2018), Kindle pp. 134, 147:
Nusantarians, protected by their seas and ships, were relatively safe on their islands from more populous mainland powers. But it is remarkable that their mainland foothold – the Cham territory – on the southern coastal border with China lasted as long as it did: from settlement, probably from Borneo, around 1000 BCE to Champa’s final extinction by Vietnam in 1832.
Champa was the political successor to the Sa Huynh culture but came under Indian cultural influence while retaining its Austronesian language and living by its seafaring traditions. At its greatest extent Cham territory ran from Vishnupura, near modern Dong Hoi, to Phan Thiet, just north of the Mekong delta. The importance of this narrow strip between the sea and the mountains lay not in its resources but in its position. Journeys from Guangzhou to Siam, Sumatra, Java, Borneo and beyond could be direct, but a stop-off point was often needed for safety. Its ports could also serve as entrepôts for goods from Borneo and Mindanao. From early trading communities there developed more organized, Hindu states, tied together, sometimes loosely, as Champa.
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Another Vietnamese advance in the early seventeenth century included the capture of Nha Trang. The Cham state was formally wiped off the map in 1832 when the Vietnamese took its last stronghold Panduranga (Phan Rang) and advanced through the hitherto Khmer-ruled Mekong delta to the Ca Mau peninsula, modern Vietnam’s southernmost point. Cham resistance to the Vietnamese continued long after the capture of its territory. Vietnamization was a slow process brought about by a mix of immigration and adaptation.
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By the time the shrunken Cham territory was finally absorbed by the Vietnamese, the majority were Muslims. Today the small Cham minority in Vietnam is divided by religion, though most are non-Muslims. Following the fall of Panduranga in 1832, many Cham Muslims fled to Cambodia, where they remain as a small minority speaking and writing Cham and maintaining such Austronesian characteristics as matrilineal descent. Some also left for Kelantan in Malaysia. Few Cham speakers are left in Hoi An, which inherited a trading tradition from the Cham and was settled by merchants from China and Japan who built the riverside town which is today a World Heritage site like My Son itself. So different in style, My Son and Hoi An are a microcosm of some 1,500 years of Nusantarian history.
Far Outliers 