A dry sea

The largest desert in the world, the Sahara, is 3.5 million square miles of sand, rock, mountains, and plateaus stretching from the Nile River to the Atlantic Ocean. The United States would fit inside of it.

Yet this expanse is inhospitable, with only a few small islands where fresh water and food enable permanent settlement. It seems more like a barrier. Describing the Sahara Desert is like describing an ocean, as many people have noted. In fact, Sahel comes from the Arabic word sāhil, meaning “shores.” How does our understanding of the Sahara change when we imagine it as a sea, linking people through the exchange of goods and ideas?

From 1200 to 1450, an extensive trans-Saharan trading system reached its peak. Huge caravans of camels and merchants transported goods from one “shore” of the desert to the other. Trade across the Sahara linked the great kingdoms of West Africa to the Mediterranean and Indian Ocean worlds.

Why would someone try and cross the largest desert in the world? The same factors that would motivate someone to hop on a wooden boat and head out across the oceans. At its most basic, the development of extensive trans- Saharan trade routes required goods of significant value. Additionally, merchants needed a cost-effective method of transportation to move those goods across the desert.

The ship of the desert

Like merchants at sea, caravans in the Sahara also faced storms and wrecks when desert winds forced them to abandon their wares or risk being stranded. Any successful caravan required experienced guides, and the best were Berbers. Some Berbers were pastoralists who lived on the edges of the desert and traveled with their livestock. Like pastoralists in Eurasia, the Berbers were essential to the growth of the trade. They captained the “ship of the desert”—the camel.

Like the development of new ships and navigation techniques in the Indian Ocean, developments in travel technologies enabled new long-distance trade routes across the Sahara. The introduction of the camel was by far the most important of these. Camels are superior to horses for desert travel because they are more suited to desert conditions. The Berbers improved to the camel saddle, allowing them to carry even larger loads over greater distances. A single camel crossing the Sahara could carry around 400 pounds of trade goods. Over shorter distances, they could carry up to 1,200 pounds.

When you think of the Sahara, you probably picture camels, but the camels native to the region went extinct during the Stone Age. Around 300 BCE, the one-humped camel was reintroduced to North Africa. Once camels arrived, the Berbers quickly began using them to cross the desert.

Saharan caravans¹ were impressive feats of organization. Usually, the merchants making their way north or south across the desert rented camels from pastoralists. Caravans set out during the cooler months from October to March, traveling at the coolest times of day. A caravan traveled around 20 miles a day, and the main routes followed water sources.

Pastoralists were essential for the trans-Saharan trade, but they were also a threat to it. While friendly groups might act as trading partners and guides, others might attack caravans. States and merchants paid tribute to pastoralists in order to ensure the safety of their caravans. By the thirteenth century, it was common for caravans crossing the Sahara to travel with 5,000 to 10,000 camels. Timbuktu, in the Mali Empire of West Africa, started out as a caravanserai, or a pitstop for caravans, before it grew into a center of learning and commerce.

A land of gold: The Mali and Songhai Empires

Many goods traveled along these trade networks, but it was the gold of West Africa and salt of the Sahara that drove the trade. Salt is necessary for human life, but it was in short supply in West Africa. Berber tribes controlled several salt mines, which allowed them to buy high-value goods like gold from merchants in West African cities. They could also purchase enslaved people in these cities. From the cities, goods and enslaved people were taken to the Mediterranean and on to Egypt. The trans-Saharan routes reached their peak from the twelfth to fifteenth centuries.

The region of West Africa south of the Sahara was home to powerful empires and large cities. Here, along the flood plains of the Niger River, agricultural societies like the Mali (1235–1670) and Songhai (1430–1591) empires thrived. These empires depended on trade across the desert to exchange their gold for salt and luxuries from the Mediterranean. The emperors of Mali and Songhai strictly controlled the movement of merchants across their land. They wanted to guard the secret locations of gold mines to the south. Their control of the trade routes enriched and expanded these empires.

Waves of change: The arrival of Islam

Powerful Islamic empires and Muslim merchants in the north united much of Afro-Eurasia into one trading system. As West Africans converted to Islam, trade expanded into the Sahara.

Arab merchants made their way across the desert to trade goods in exchange for gold in West Africa. West Africans also traveled north. Many of them were enslaved.² But plenty of West Africans made the journey voluntarily, many traveling on pilgrimage to Mecca.

Caravans and merchants carried abundant wealth, goods, and people across the Sahara. But perhaps the most important thing they carried weighed nothing at all: Islam. Islam was the most important factor in the expansion of trans-Saharan trade. After the Arab conquests of the seventh century, the Berbers converted to Islam. As trade expanded, many West African merchants converted as well. Arabic provided a common language and value system, making it easier for traders to communicate, trust each other, and record their transactions.

In West Africa, Islam became the religion of urban elites because it spread first to cities. Most converts lived in cities and were merchants or members of the ruling class. Since most of the population was not urban, local religions remained more important long after the arrival of Islam.

New routes

The combination of increased trade, cross-cultural exchange, and Islam created a golden age for the empires of West Africa, allowing cities to flourish. Trade allowed travelers and scholars to move around the world, exchanging knowledge. Mansa Musa, the ruler of Mali, made the Hajj to Mecca in the 1320s. He traveled with tens of thousands of camels and servants, carrying a fortune in gold. He spent so lavishly that he destabilized the Egyptian economy. His displays of wealth helped create myths that West Africa was a land where gold grew like plants in the ground.

Europeans began exploring the West African coast partly due to such myths. During the fifteenth century, Portuguese sailors looked for a route around Africa to the Indian Ocean trade. They established new sea lanes bypassing the Saharan routes. But large caravans continued to cross the desert right up until the early twentieth century.

1 A caravan is a group of people travelling together for protection, often for religious pilgrimage or trade. Caravans were common on the overland trade routes of Afro-Eurasia.
2 Slavery in this era had little to do with race or skin color. West African slaves were usually prisoners captured in war. White people from the Caucasus joined black people from East and West Africa in enslavement in the Mediterranean and Indian Ocean markets.