The Indian Ocean Trade Network and the Swahili Coast

Core Idea

Between about 1200 and 1450, the Indian Ocean held one of the world's largest and busiest networks of long-distance sea trade. Sailors used the monsoon winds, which blow from the southwest in summer and the northeast in winter, to make regular voyages between East Africa, Arabia, India, Southeast Asia and China. Port cities such as Kilwa, Calicut and Malacca grew rich, and merchant communities spread goods, Islam and new cultures along the coasts. The Swahili city-states of East Africa, with their Bantu-based language and Muslim merchant elite, are a clear example of a culture formed by this exchange.

How It's Best Learned

Draw the monsoon wind pattern on a map and work out when a ship from Gujarat could sail to East Africa and when it could return. Make a chart of goods by region, such as gold and ivory from Africa, cotton cloth and pepper from India, spices from Southeast Asia, and silk and porcelain from China. Compare the Indian Ocean with the Silk Roads by cost, volume and who controlled the routes.

Common Misconceptions

• One empire controlled Indian Ocean trade before the Portuguese arrived. (No single state dominated the ocean; many independent ports and merchant groups competed, and most trade was not backed by navies.)
• The Swahili city-states were Arab colonies in Africa. (Swahili towns were African communities whose language is Bantu, though Muslim traders from Arabia and Persia settled there, intermarried and added many Arabic words.)
• The Ming voyages of Zheng He set up a Chinese trading empire in the Indian Ocean. (The seven voyages between 1405 and 1433 displayed Ming power and collected tribute, but the court ended them and did not found colonies.)

Explainer

When you studied the Silk Roads, you saw goods carried overland by camel caravans across Central Asia. The sea routes of the Indian Ocean did similar work on a larger scale. Ships could carry far more cargo than camels, and the sea had no mountain passes to guard.

The key was the monsoon. In summer, winds blow from the southwest toward India; in winter, they blow from the northeast toward Arabia and Africa. A merchant could sail from Gujarat to East Africa on the winter wind, trade, and wait for the summer wind to carry him home. This made voyages regular enough to plan around. Arab and Swahili dhows, Indian vessels and large Chinese junks all used these routes. Tools such as the compass, first used in navigation in China, and the astrolabe helped sailors find their way.

Each region supplied different goods. East Africa exported gold, much of it from the Zimbabwe plateau, along with ivory and enslaved people. India produced cotton cloth and pepper. The islands of Southeast Asia grew cloves and nutmeg. China sent silk and porcelain. Ports grew at points where routes met: Kilwa and Mombasa in East Africa, Aden and Hormuz near Arabia, Calicut in India, and Malacca on the strait between the Indian Ocean and the South China Sea.

Merchants settled in foreign ports, married local women and formed communities. In this way Islam spread along the coasts of East Africa, India and Southeast Asia, mostly through trade rather than conquest. On the East African coast, these contacts produced Swahili culture. Swahili towns built mosques of coral stone, their rulers were often Muslim, and their Bantu language took in many Arabic words. The traveler Ibn Battuta visited Kilwa in 1331 and praised it as a fine city.

In the early 1400s the Ming emperor sent Zheng He on seven great voyages, some reaching East Africa. They ended in 1433. In 1498 the Portuguese navigator Vasco da Gama reached Calicut, and the Portuguese soon tried to control the ocean by force, a sharp break from the older pattern of open, competitive trade.