How did the portuguese establish footholds in on the african coastlines and far reaching effects did they have on africa ?

The correct answer is by building small forts and trading post.

The Portuguese established footholds in on the African coastlines by building small forts and trading post.

After Portuguese explorer Vasco da Gama reached the Cape of Good Hope and get to India to collect a ship cargo of Pepper, the Portuguese built forts and trading post in the west and east to help their ships during the long sailings. There were ports in Africa, in India, in China, and in Japan. This way, Portugal benefited more doing this than establishing permanent colonies, in its attempt to strengthen its spices trade.  

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