From Empire of the Winds: The Global Role of Asia’s Great Archipelago, by Philip Bowring (I.B. Tauris, 2018), Kindle pp. 67-73:
We do not yet know how products from Nusantaria came to arrive at the plush homes of a literate, urbanized Babylon. But that merely says how little we know about unwritten history. Sailing techniques which took Austronesians to Samoa were equally capable of taking them to the west coast of India where people from Harappa, the city of the Indus valley civilization which flourished between about 4500 and 3900 BP, had a settlement in Gujarat. At the least, sailing to the south-east coast of India from Sumatra or the Malay peninsula would have been well within their reach. There is evidence that the single outrigger sailing craft found in southern India was brought from the east around this time. The use in Arabic and Persian of Dravidian- rather than Sanskrit-derived words for Indian items such as ginger and rice indicates very early south Indian connections, and Nusantarians may also have taken coconut cultivation to Sri Lanka and southern India.
Other indications of trade links between the eastern archipelago and the west come from ancient Egyptian, Hebrew and Greek sources. An Egyptian text from around 1500 BCE refers to an expedition to the Land of Punt, most likely a kingdom on the Horn of Africa and source of various exotic products including gold, ivory and fragrant woods from tropical regions, possibly a reference to aloeswood which came only from the islands, peninsula and the far south of China. The expedition also returned with an item believed to be cinnamon, possibly from south India but more likely from the Malay peninsula or Sumatra. There are also Hebrew references to cinnamon from the seventh century BCE and a Greek one from the fourth century BCE. Hebrew texts from the time of King Solomon (around 950 BCE) make references to sandalwood, which may have come from south India, but the best came from drier places like Timor in the eastern archipelago. The first century CE Jewish historian Josephus mentioned trade expeditions sailing to the east from the Red Sea which took three years to complete.
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Roman ships, built of cedarwood planks and with pitch caulking and lead-lined hulls, carried an average 220 tonnes of cargo according to the Musiris document but could be up to 35 metres in length with a deep draught and have a capacity of 350–500 tonnes.
Major Roman exports were wine, glassware and metals, but imports were invariably greater in value, so the difference had to be paid in silver. In addition to luxury items such as ivory, tortoiseshell, pepper, frankincense and silk, the Romans even imported special sands from India and Africa to facilitate the cutting and polishing of marble for their many magnificent buildings.
The Romans had several trading bases with semi-permanent settlements on the Malabar coast of India, and at least one on the Coromandel coast: Arikamedu, near Pondicherry in Tamil Nadu. This was active from the second century BCE or earlier until the third century CE. Although trade would have suffered as Roman power declined in the face of rebellions and the onslaughts of Germanic tribal confederation, access to the east remained on such a scale that large quantities of pepper and silk were among the demands of Visigoth leader Alaric in return for not sacking Rome in 408.
Far Outliers 