The Bantu migration was important because the Bantu introduced things like iron working, new crops and centralized administration to other cultures. The Bantu also brought with them methods of building permanent homes.
The Bantu migrated for a number of reasons. There were several internal conflicts among individual Bantu tribes, and there was constant aggression from those not part of the Bantu. Their population grew so quickly that the Bantu found themselves faced with overcrowding. All of these things caused the tribe to migrate to try to find a better life.
Although the migration resulted in many positive things, it also had negative repercussions. The Bantu suffered a loss of language and culture, and the population suffered severe depopulation.