In 1750 the African continent had seen its share of colonialism, but it still has some sizeable independent nations as well.
In north Africa, the influence of the Ottoman Empire is strong. Egypt is an Ottoman client nation, while the Barbary States of Tripolitania, Tunisia and Algeria are rogue states that were often supported by the Ottomans and engaged in continual piracy in the Mediterranean, seizing European loot and slaves. On the far west, Morocco remained independent as a bridge between east and west. North Africa has always been a zone of conflict between the European and Arabic cultures and can be expected to remain a hotspot of diplomatic tension.
West Africa was first explored by the Portuguese, after which Europeans have continually fought for dominance over the coastline with varying success. The climate and wilderness made it hard for Europeans to survive and old African kingdoms still dominate the mainland. The Slave and Gold coast are in the hands of the Aro Confederacy, Dahomey Kingdom, Benin Kingdom and Ashanti Empire, while European nations try to maintain trading forts there, especially for the purchase of slaves.
Further down the west coast the Kingdom of Kongo remains independent, while the Portuguese have successfully created a client nation of Angola with African nobility. In south Africa the Dutch created an outpost for re-supplying trade ships, but the lands still remain largely unexplored.
Eastern Africa has very different cultural influences. Wild Madagascar is dominated by the Merina Kingdom, which has distinct tribal Asian roots, while Portugal controls the client nation of Mozambique. Further north the Arabic culture dominates, with independent African Sultanates of the Geledi, Warsangali and the Hiraab all the way towards the Red Sea, where Ottoman influence rules supreme.