What was shared by each of the kingdoms of the Sahel?

The kingdoms of the Sahel, such as Ghana, Mali, and Songhai, shared a rich cultural and economic heritage characterized by trade, particularly in gold and salt. They were interconnected through extensive trade routes that facilitated the exchange of goods, ideas, and religions, notably Islam, which influenced their governance and culture. Additionally, these kingdoms exhibited similarities in social organization and political structures, often centralized around powerful monarchies that controlled trade and promoted cultural exchange.