How did the Susu and Malinke expand into the area of modern Guinea around 900 CE?

Around 900 CE, the Susu and Malinke (Maninka) peoples began to encroach upon the territories of the Baga, Koniagi, and Nalu populations who had long inhabited the region of modern-day Guinea.12

This movement marked the beginning of a broader trend of migration and expansion by Mande-speaking groups into the area. These groups often moved as traders or conquerors, seeking to organize local populations into petty kingdoms and gain access to coastal resources, such as salt and, later, foreign merchandise from European sea traders. This process of expansion and incorporation continued into the mid-13th century, when the towns and villages of Upper Guinea were integrated into the Mali empire.312