Africa's Slave Trade to Colonialism to Liberation / The history behind Africa's slave trade, how it started, and where in Africa it began first. African chiefs used to sell their own people in exchange for valued goods, or treasured assets. Then, when the Europeans arrived they began trading with them. The Europeans offered what they had in exchange for slaves and the slave trade became a widely known, and relevant phenomenon in most parts of the world. America and Europe needed people who could do hard labor, who could do their work for them which were rigorous tasks. Slave traders came along the African coast, which was the Sub-region (South of the Sahara) to acquire slaves. They would get them in large numbers and pack them inside the ships they came with. Then, in the 1800s the slave trade was abolished by Abraham Lincoln and then European colonialism/imperialism became the new system in which mainly the Europeans created to strengthen their nations. The necessity of raw materials, namely natural resources, led to European colonization. Also, to establish colonies which were brought up in the ways of the colonial powers, particularly Britain, France, Belgium, Portugal, Germany, among others in order to extend their influence both culturally, politically, socially, and religiously. The geographic borders one sees on the map today of Africa, were designed by the European colonial powers who wanted to divide the continent into sections whereby it would be clear who's colony was where, and that each colony would stay within boundaries. This was carried out in 1884 in Berlin, Germany. Africa's resources were being exported immensely to the nations which ruled over certain colonies there, thus being distributed out to the rest of the world. After World War 2 and the establishment of the United Nations, nationalists movements began which internal self government came into focus and practice, thus leading to independence, sovereignty, and the emancipation /liberation of the African continent. Pan Africanists/nationalists/freedom fighters like Dr. Kwame Nkrumah, Patrice Lumumba, Sekou Toure, among others came into being and agitated for independence.