Ancient trade crossed the northeastern edge of the Sahara in the Naqadan period. Predynastic Egyptians in the Naqada I period traded with Nubia to the south, the oases of the Western Desert to the west, and the customs of the eastern Mediterranean to the east. Many exchanging tracks went from oasis to oasis to resupply on both food and water. These refugees were very significant. They also shipped obsidian from Ethiopia to form swords and other things.
Trade along the silk roads and the trans-saharan trade routes resulted in "4. cultural diffusion between different societies" It also led to increased profits for the western and eastern states.
The two rival group include Hutus and Tutsis The Hutus are farmers in the fertile hills and valleys of the present day Rwanda and Burundi The Tutsis are cattle herder who migrated to Rwanda and Burundi and were from kenya about 400 years ago
