Portuguese language in Africa more recent migrations of refugees (some of whom speak Portuguese) to neighbouring countries such as Democratic Republic of Congo, Namibia, Zambia and South Africa. Other migrations involved returning Afro-Brazilian ex-slaves to places such as Nigeria, Benin, Togo, Angola and Mozambique. There are also some returning white Portuguese African refugees and their descendants from Brazil, Portugal, and South Africa to their former African controlled territories, mostly to Angola (up to 500,000) and Mozambique (350,000), and most importantly, there is the arrival of Portuguese post-colonial expatriates in Angola in the recent years, because of Portugal's economic interests and the Angolan economic boom.
West Africa this land is plains lying less than 300 meters above sea level, though isolated high points exist in numerous states along the southern shore of West Africa. The northern section of West Africa (narrowly defined to exclude the western Maghreb) is composed of semi-arid terrain known as Sahel, a transitional zone between the Sahara and the savannahs of the western Sudan. Forests form a belt between the savannas and the southern coast, ranging from 160 km to 240 km in width. The northwest African region of Mauritania periodically suffers country-wide plagues of locusts which consume water, salt and crops on