That's how the world started out beginning with scientific Adam & Eve's Great Grand Children Separated themselves into clans, villages, & tribes resulting from over crowding & depletion of resource ensued competition, rivalry, subjugation, slavery, theft, rape, child rape, incest, human sacrifice, murder, raiding, & warfare. Slavery has been part of N. Africa, the Arabian Peninsula, & Persia before civilization sprang up in the fertile crescent. Sub Saharans are no exemption, but had very limited contact with Kingdoms within or around the fertile crescent as the Great Sahara Desert prevented easy access. Ancient Egypt never went beyond N. Sudan & Abyssinia to wage war to harvest slaves. Camels originating from Mongolia enabled small trading scouts of Muslim slave traders to penetrate the Great Deserts as they slowly establish routes to Oasis within the desert penetrating the Sahel from 1000CE-1200CE into the interior of Sub Sahara along the Coast. Timbuktu was a slave Port founded by Arabs that also served as a library to spread Islam to the Elites that the Arabs were trading with for slaves. (Academics wasn't indigenous to Sub Saharan Africa. Arabs & Europeans brought Academics to Sub Saharan Elites)
Chinese fore & aft sails, rudder, compass, gun powder & cannon (allowing them to expel the Cordova Caliphate from Spain) reached Europe through travelers & merchants such as Marco Polo, reversed engineered & improved over time enable Europeans such as the Portuguese to circumvent the Sahara desert to establish trading port with the coastal villages & hunter gathering Kingdoms on their (Portuguese) way to India.
Turkey was the first among Islamic States to Abolish Chattel/Caste Slavery for European Descent & Sub Saharan Descents in the 1880s. The Slave Culture is still alive in Islamic states throughout the middle east trough Immigrant Sponsorship with immigrants usually unpaid, abused, raped & beheaded. Slavery is pretty much hidden & Islamist like ISIS, Al Qaeda, Boko Haram wants to revived the practice openly as it was 55-60 years ago. Traditional Slavery still exist among sub Saharans. Slaves weren't just obtained through warfare & raiding campaigns which also involved rape & mutilations, but also offering ones virgin tween daughter as payment for an offense to another family or spirits for which the spiritual leader receives the pubescent girl as his slave in labor & sex. Child trafficking is huge business in the Sahel, N Africa, Nigeria, Arabian Peninsula... South Africa being a Corrupt Rape & Murder Capitol of the World for 2 decades stems from hunter gathering tribal culture deeply rooted within the tradition & society of Sub Saharans since scientific Adam/Eve in Africa.
With the arrival of Arabs (1000CE-1200CE) in the interior of Sub Sahara & before the Portuguese (late 1400s) sailed around Africa to set up slave trading ports with costal bush kingdoms, tribal warfare controlled population through sacrificial ceremonies that may involved having to consume sacrificial offerings, a practice that still exist.
Joshua Milton Blayhi (Gen. Butt Naked) being notorious for conducting these sacrificial ceremonies as its High Priest in Liberia (VICE: Cannibal Warlords). In Tanzania Albino's, mostly children, are killed for their body parts as charms, souvenirs, & even consumed in the same manner that Gorilla hands and feet are sold as charms or souvenirs, the rest being consumed in the beliefs of gaining some powers like Black Panther's heart of herb.
After abolition of slavery swept Europe (serfs), N. Americas, then central & S. America 30-40 years later, Sub Saharan Bush Kingdoms, later republics, still had a reliable slave trading partner with Arab & Arabize nations for another 100-140 years (Saudi Arabia (1964), UAE (64), Zanzibar (64), Mauritania 2007).
Sub Saharans never matured to developing a written language, farming, academics & technologically advance civilizations to rival great Middle Eastern, East Asians, & Europeans civilizations from Ancient to Medieval times. Academics, Farming, & Iron technology were brought to Sub Sahara by Arabs & Europeans. If Sub Saharans had never made contact with Arabs, Chinese, & Europeans, they would have remained as the N. Sentinelese Islanders have.
Middle Eastern Civilization had a head start in building Civilization in the Bronze Age, but was surpassed by Asians & Europeans shortly after In the Iron Age.. At the advent of the industrial revolution due to Newcomen & Trevithick's Steam engines & locomotive (external engine) is where European Civilization took off, but it was the Internal Combustion Engine (Automotive, Aircraft, Jet) & Alternating Current that really turbo boosted European Civilizations in Europe, & Europeanized N. America (USA) & Australia leaving every great civilizations way behind, until if & when China reclaims it in the future as China, followed by Japan & Korea closes the gap. Amerindians built their own impressive civilization, but were still far behind middle Eastern, Asians, & Europeans due to the lack of Iron tech/metallurgy, written language & the wheel until contact with Europeans. Sub Sahara Africa was way behind everyone else. Feelings may be hurt, but facts are facts everyone should accept their short comings & others great achievement to grow in maturity & move forward.
The Sahara desert prevented Sub Saharan contact with the middle east civilization (Sumer, Mesopotamia, Persia, Anatolia, Assyria, Egypt). The planting of crops & the written language (cuneiform, Taiji (Chinese characters), Sanskrit, Indo European Alphabet) to record the crop yields in Farming Developed in the Fertile Crescent 8,000 BC., Southern Europe & Mehgarh (Pakistan) by 7,000 BC, Asia (China) was Farming Rice & Planting in Rows by 6,800 BC, Ireland & Central Europe by 5,500 BC. Domestication of Horses in the Eurasian Steppes & the Development of Oxcart vehicles by 4,000 BC., Egypt & Thailand farmed by 4,000 BC, India by 3,000 BC. The first great civilization to arise from these Farming Revolution was Sumeria & Mesopotamia. They developed the Chariot for warfare 2500 BC the Oldest Real Wheel-Axle Combination dates back in 3150 Eastern Europe. From Copper, Tin, & Bronze gave Sumeria an edge over nearby kingdoms, but also spreading the metal indirectly which allowed Greece & Persia to conquer the Middle East & Egypt. Europe & Asia surpassed them with Iron. East Asia, BC era,(China) cast iron industrialization, carbonized & chrome plating steel swords with the use of double piston bellows. India developed Damascus blade for beauty & some strength in the middle Ages. Japan created the strongest & sharpest steel swords before Bessemer employed 2 Chinese Metallurgist from China to develop his Bessemer process industrializing steel production. Egypt had Hieroglyphs, but Sub-Sahara Africans never created or adopted a written language of their own until Arabs (1000-1200 AD/CE) then 4 or 5 hundred years later Europeans, brought & taught their Alphabets (Aramaic/Italic) to assimilated Sub Saharan Hunter Gathering or pastoral (N/E Africans) Elites. Sub Saharan Contact with Ancient Egypt (Arab) or Arabia were limited to Sudan & Northern shores of the horn of Africa where Ancient Egypt & Arabia harvested their slaves from. If they had gone further south into the Interior of Sub Sahara, they'd have had it easy to colonize & assimilate Bush Kingdoms of Sub Sahara.
China's Wealth & Influence were due to their technology in Porcelain, Silk, Gun Powder 400 AD/CE, Crossbow, Seed Drill, Industrial Cast Iron Plow, Cannon, Drill Mining, Rudder, Chain Pumps, Stirrups, Horse Harness, Compass, Moveable Type Printing, Pasta... that reached Europe through the Silk Road, the Middle East, & the Indian Ocean. Europe being in constant warfare had to keep innovating & with the Arrival of Chinese Iron Technology in Cannons, Match Lock, Crossbow, Iron Plow..., Europe Reversed Engineered Chinese Technology & kept improving upon them to Match China in their Global Status until Completely over taking China's Great Civilization in their Global Status (notably Britain).
Europeans independent written language is how Europeans establish their own independent Academics in Literature, Grammar, Art, Engineering, Mechanics & modern Science into the Industrial Age through the Computer & Space Age. The Chinese, Indians or Turks didn't teach them these things through Affirmative Action. Although Hindu Arabic numerals & decimals originating in the Middle East & India region/area (1100CE), Europe was able to Build Pantheons, Castles, Domes, Colosseum, & Arches without It using Roman Numerals, Geometry, measurement, & Mathematics independent from other Civilization. When the Hindu Arabic Numerals did arrive in Europe 1100 AD, it enabled Galileo, & Isaac Newton to develop a new form of Mathematics called Physics that spawned, Calculus & Quantum Physics. Europe had astronomy before Marco Polo came back with the compass..
Europe tried to develop Sub Sahara Africa with their tech, medicine, writing/documentation & system of governance, Now China is trying to finish where Europeans left off. Angola may become the Wakanda that Africans never built. Sub Saharan Countries just wait hand & foot for Oriental & Europeans to Improve, Maintain, & Jump start the Infrastructure brought & put in place by People of European descent that Sub Saharan are currently miss managing into ruins.
What Sub Saharan Africans truly need to be successful independently is to have a majority (75%-80% at the most, if not 100%) of the population responsible, self reliant/independent, accountable, honest, honorable & controlled population growth which is necessary for stability & prosperity of 3rd world countries.