How did the trans atlantic slave trade affect west african peoples who were not enslaved

The trans Atlantic slave trade was a very dark period in our recent history from the late 17th century to the early 19th century. It was a cruel enterprise and even though there were many attempts from righteous people during this time to stop the practice, they were mostly unsuccessful.

The remaining people in Africa who were not themselves slaved, ended up one way or another participating in the lucrative slave business.  The trade affected various groups of people in different ways. Some of the groups or societies benefited economically while other groups in the interior of Africa suffered negative consequences, because they were selected to be taken as slaves. Specially those living in the coastal areas.

The societies were categorized in this manner:

1) Societies which were mainly the object of slave raids or slave producing societies.

2) Societies which were mainly engaged in the practice of capturing slaves to supply the markets.

3) Societies that mainly engaged in the sales of slaves. They acted as middle man or retailers, selling  the slaves to European buyers.

the fact that could also be added to column b is that during world war ii, specifically between the years 1941 and 1945, japan expanded its territory towards the indonesian territory in what was known later as part of the "pacific war". in that time, japan could conquer the philipines, singapore,   borneo, central java, malang, cebu, sumatra and various other islands of the area, therefore expanding its territory for a brief period of time.