From Empire of the Winds: The Global Role of Asia’s Great Archipelago, by Philip Bowring (I.B. Tauris, 2018), Kindle pp. 117-119:
Srivijayan dominance of Nusantaria was for a long time bolstered by cooperation with fellow Buddhists in central Java, the Sailendra dynasty. Indeed, Srivijaya’s dominance attained its greatest geographic reach following the linking of Sailendra power to Srivijaya’s through a dynastic alliance. The Sailendra’s economic contribution to the alliance was greatly aided by Java’s ready access to the Spice Islands, which added to its agricultural wealth, and by its relatively large population. The Sanskrit name ‘Sailendra’ means ‘Lord of the Mountain’, a reference to the towering volcanoes such as Mount Merapi [Gunung Merapi ‘Fire Mountain’], which overlooks the great Buddhist shrine of Borobudur which they built. Although their power base was in Java, the Sailendras were Malays from Sumatra. This explains the use of old Malay, not Sanskrit or Javanese, for some of their inscriptions.
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Java, known as Yavadipa, had originally been a centre of Hinduism which reached its peak in the seventh and early eighth centuries. Its spiritual base was the Dieng plateau, literally ‘Mountain of the Gods’ in Sanskrit. The plateau is reached from the plain through a series of rich valleys and then by a narrow mountain passageway to the 2,000-metre high caldera of an extinct volcano, which still has sulphurous springs. Here there were sacred bathing sites and the centre of a cult of Shiva, the god of fertility. It was once the site of some 400 temples of which only eight survive, the oldest stone structures on Java.
The Dieng plateau’s best recorded patron was the early eighth century ruler Sanjaya, who erected a sacred lingam in praise of Shiva, invoking the spirit of his ancestors and noting how in learning and harmonious government he ‘had his feet high above the other kings of good family’. He was titled both a Ratu – the Austronesian noble title found from Fiji to the [Malay] peninsula – and a Maharaja, the Indian king of kings.
The history of the relationship between the Sailendras and Javanese Sanjayas is unclear, but at some point they were joined by marriage alliances in which the Sailendras were dominant; however, despite their Buddhism the Shiva worship of the Sanjayas lived on. Indeed, loyalty to the Sailendras was more important than choosing between Shiva and Buddha.
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The Sailendras also extended their power outwards. Using Srivijayan seapower they conquered Indrapura, the leading Khmer city, and in 802 installed the Khmer prince Jayavarman II as ruler. (He later rejected fealty to the Sailendras and moved his capital inland to Hariharalaya, south of Siem Reap. He reigned for nearly 50 years and initiated what became the Angkor dynasty.)
The Sailendras were also sometimes in conflict with the Cham, who competed for some of Srivijaya’s China trade. The Cham were not only closest to the great China market, they also had sea links to Borneo and the Philippine islands, from which they could source some of the forest products in demand in China. An eighth century Vietnamese account describes people from Java and Sumatra raiding as far north as Tonkin. A Cham account in Sanskrit of the same era, found at Nha Trang, described how in 774 ‘men living on food more horrible than cadavers, completely black and gaunt, dreadful and evil as death, came in ships’ and burned a temple and stole the lingam before being beaten off by Satyavarman. These might have been orang laut engaged in freelance raiding or have been encouraged by Srivijaya because, only a few years later, in 787, ‘the armies of Java’ came and destroyed another temple. More generally, however, the era saw the strengthening of its trading and settlement posts including Manila bay and Sulawesi.
Far Outliers 