Answer:
They needed more land for a growing population.
Step-by-step explanation:
The Bantu were an African group of people who spoke various dialects of the Bantu language. These people originally came from the area around the Niger River in southern West Africa. From this region, they expanded throughout central, eastern and southern Africa. They took their traditional practices, language and technology with them, influencing the whole continent. However, the precise dynamics of the migration, as well as the specific reasons for it are not well-known.