Why the sea mattered
Camels make better pictures, but ships carried more. A single merchant ship could hold the load of hundreds of camels, and it did not need oases, passes or tolls at every kingdom. Historians increasingly speak of a maritime Silk Road running from the Red Sea and Persian Gulf across the Indian Ocean to India, Sri Lanka and Southeast Asia, then north to the ports of southern China. Sailors timed their voyages to the seasonal monsoon winds, and port cities grew up where ships waited for the wind to turn.
A merchant's guidebook
Our best early window on this trade is the Periplus of the Erythraean Sea, a Greek merchant's guide to Indian Ocean ports, written by an unknown author in the middle of the first century AD. "Erythraean Sea" meant the waters from the Red Sea to the Indian Ocean. The Periplus lists harbors in Egypt, Arabia, East Africa and India, notes which rulers controlled them, and advises what to bring and what to buy: wine, coral and coins to sell; pepper, pearls, ivory, cotton cloth and silk to bring home. It mentions a land called Thina far to the north, from which silk came overland, the first Western hint of China by name.
Pepper drew Roman ships to Muziris, a port on the Malabar coast of southwest India. A papyrus from the second century AD, now in Vienna, preserves a loan contract and a cargo list for a ship returning from Muziris. The cargo, mostly pepper and ivory, was valued at a sum large enough to buy a sizable estate in Egypt. Such evidence explains the Roman coin hoards found in southern India.
Southeast Asia's gatekeepers
Ships passing between India and China had to go through Southeast Asia, and states there grew rich by controlling the passage. From the seventh to the eleventh century the kingdom of Srivijaya, based at Palembang on Sumatra, drew its power from control of the Strait of Malacca, the narrow channel between Sumatra and the Malay Peninsula. Srivijaya was also a center of Buddhist learning; a Chinese pilgrim, Yijing, studied Sanskrit there in the 670s on his way to India.
Control of chokepoints invited rivals. In 1025 Rajendra I of the Chola dynasty, a powerful kingdom in southern India, launched a naval raid that sacked Srivijaya's ports. Trade policy, then as now, could lead to war.
Sewn ships and a sunken cargo
Many Indian Ocean vessels were built without nails. Their planks were sewn together with coconut fiber cord, which made hulls flexible in heavy seas and easy to repair with local materials. In 1998 fishermen diving off Belitung, an island in Indonesia, found the wreck of just such a ship, probably built in the Arabian or Persian Gulf region and lost in the 830s. It carried about sixty thousand objects, including gold and silver, but above all tens of thousands of Changsha bowls, glazed stoneware made in southern China. One bowl bears a date corresponding to 826. Many were decorated with designs aimed at buyers in the Islamic world, which shows Chinese potters producing in bulk for distant markets.
The wreck was recovered by a commercial salvage company and sold to Singapore, where it is displayed. When the Smithsonian planned an exhibition in 2011, archaeologists objected to the commercial salvage, arguing that it destroys context and rewards treasure hunting, and the show was shelved. The question of who should own sunken heritage remains open.
Ports and port peoples
Chinese ports such as Guangzhou, and later Quanzhou, which foreign visitors called Zaytun, hosted communities of Arab, Persian, Indian and Southeast Asian merchants with their own mosques and temples. Such diversity could be fragile. When rebels took Guangzhou in 878, Arab writers reported a massacre of foreign merchants, though their figures cannot be checked.
From the other end come the papers of the Cairo Geniza, a storeroom in a Cairo synagogue where Jews deposited worn writings. Among them are letters of Jewish traders who worked in India in the twelfth century. One, Abraham Ben Yiju, a merchant from Tunisia, lived for years on India's southwest coast. He freed an enslaved Indian woman named Ashu and married her, and their children later appear in family letters.
Worked example: what one bowl tells us
Pick up a single Changsha bowl from the Belitung wreck. Its shape and glaze show it was made in a kiln complex in Hunan, far inland, so it traveled by river before reaching a port. Its decoration, with Arabic style lettering or Persian motifs, shows that potters knew what foreign customers liked; information flowed back along the route as well as goods. The fact that tens of thousands of nearly identical bowls were packed in jars shows mass production, not luxury craft. The ship's sewn hull shows that a West Asian vessel sailed all the way to China and was heading home.
Put together, the bowl overturns a common picture. The maritime Silk Road was not mainly about rare treasures carried by daring adventurers. It was a regular commercial system in which ordinary goods moved in bulk, makers designed for overseas tastes and many peoples shared ports. Yet the bowl's path into a museum also raises a modern question about whether heritage should be sold to the highest bidder.