The geographical location consisted of favorable conditions within basins, valleys, rivers, and lakes. But with the shrinking of Lake Chad forced much of the population of the Sahara into the sahel. Thus, exploration for goods and useful resources was brought about, and trade routes were established. This would lead to a flourishment of goods that contributed to the introduction of new ideas such as Islam. Islam was introduced into Sudan from North Africa and was mainly a product of the trans-Saharan trade. For instance, Timbuktu was an important center for Muslim traders and scholars. Islam was foundational in establishing Timbuktu, and in doing this, commerce was successful and highly stimulated. Since West Africa was a key trading area, Muslim traders/merchants from North Africa helped spread the religion into Sudan. Thus, those in Western Africa began to convert to Islam and enjoy wide-ranging contracts with the non-African Muslims. Due to their geographical location of West Africa, the importance of trade made the Sudanese rulers take steps to guarantee the security and freedom of worship of North African traders within their Kingdoms. Geographically we see how religion impacted the use/availability of trade within Africa that would prove to be crucial for West African Empires