The gold-salt trade was an exchange of salt for gold between Mediterranean economies and West African countries during the Middle Ages. West African kingdoms, such as the Soninke empire of Ghana and the empire of Mali that succeeded it, were rich in gold but lacked salt, a commodity that countries around the Mediterranean had in plenty. Salt was important for replacing fluids and preserving food in the tropical climate south of the Sahara.
The Soninke empire of Ghana, named the "Land of Gold" by Islamic scholars, is linked with the rise of the trans-Saharan gold trade that began around the fifth century. Countries in North Africa needed gold for coinage, and they got their supply from Berbers who traveled across the Sahara in camel caravans carrying blocks of desert salt. The trade lasted for centuries, and was partially responsible for the introduction of Islam to the Berbers, and consequently West Africa.
The Soninke maintained exclusive control over the gold trade by keeping the location of gold mines a secret. In the 11th century, the empire was strong enough to take over the Berber town of Audaghost, an important terminus along the trade route. However, a century later, new routes bypassed Audoghost and moved toward newer goldfields. The Soninke empire soon lost its domination of the gold trade.
The Mali empire that followed, and the Songhai empire that rose later, continued relying heavily on the gold-salt trade.