The kings of ancient Ghana amassed wealth through the gold and salt trade, aided by the development of ironworking. The kings collected taxes on trade and prohibited others from owning gold nuggets, which limited the availability of gold and kept prices high.
During its height, ancient Ghana was so wealthy that even pets wore ornaments made of gold, and livestock slept in luxury. Located in what is today's Mauritania, Mali and Senegal, ancient Ghana's primary natural resource was gold. At some point in its history, Ghana had expanded to include control of land between the upper Niger and Senegal Rivers, an area that is rich in gold. Ancient Ghanaians traded gold, slaves and ivory for salt from the Arabs and obtained horses, swords, cloth and books from Europe and the West. Islamic merchants traveled for over two months through the desert to reach Ghana, where they were taxed not only on what they were importing but also on what they were exporting.
The Almoravids, a Muslim group, attacked the capital city of Koumbi Saleh during the 11th century. Although Ghana repelled the invasion, 200 years later it was severely weakened by further attacks and was cut off from the international trade routes. Eventually Ghana was absorbed by the expanding Mali nation.