From the 7th century onwards, the majority of peoples in North and West Africa converted to the Islam. By trading with Arabic nations great wealth was achieved in the regions between the Atlantic Ocean, the Sahara desert and the river Niger. Gold, ivory and gemstones from southern Africa were traded for salt, spices, porcelain and weapons. Soon also humans became objects of trade between African and Arabic peoples, as well as the Berber people. The Arabs started human hunting and enslaved the people from the interior of the continent. Large trading empires emerged in the west and south of the continent. Between the 7th and 9th century, Princedoms developed into kingdoms in West Africa and into influential trading empires in southern Africa. In the course of Africa’s colonisation, new kingdoms originated. Some of them are still in power today.