The first European to reach Timbuktu was Rene Caillie in 1828. Maybe. Of course you have only 'reached' somewhere, if you get there and you get back. A little like academics who discover branches of knowledge need more than a couple of people to read their papers, and popularise the ideas. If you can't communicate or implement ideas, are they ideas? The richest man to have ever lived came from Timbuktu. Mansa Musa reigned from 1312-1337. The story of his riches became legend, but ideas spread faster than the ability of Europeans to get there and back. Mansa Musa himself made a pilgrimage to Mecca. On his way flooding the economy of Egypt with so much gold, it took decades to recover from the inflation. Lots of money. Same amount of stuff. Stuff worth less. Gold & money was and is just a way of counting.
So a full 500 years before a white face 'discovered' Timbuktu, it was at its peak. Very much connected with the rest of the world. It became a permanent settlement in the 12th century and flourished in the salt, gold, ivory and slave trade. During its Golden Age, it was the centre of scholarly learning. The wealth supporting a community of people looking at the finer aspects of life.
Down South, Tippu Tip the Swahili-Zanzibari trader built an empire on the back of ivory and slave trades. Before the European age of discovery, there was an almost 1,000 year engagement between the expanding Arab/Muslim world and Africa. And interaction between the Arab world and India and China. Tip was apparently amused by David Livingstone, the 19th century Scottish explorer. He lived a life of virtual poverty alongside the Arab-African traders but had seen more of Africa than any of them. They expanded slowly with raids for ivory and slaves. Growing over the course of years, decades, and centuries. The newly arrived European explorers pushed deep, but light. If they survived the diseases and didn't get killed, they took stories back to London.
I have often thought of the similarity between the Afrikaans and the Zulu/Xhosa/Ndebele/Swazi histories. Farming cultures who deeply value identity and independence. Who left and started again rather than being bossed around. A comparison I hadn't thought of is between the Arab World and Rome with the people on the periphery. The Franks, Germanic Tribes and the people of Britain were the Barbarians outside of Rome. The eventual sackers of Rome, but outsiders. The 'Age of Discovery' in Southern Africa was kind of a (not so friendly) hand shake between people on the outside of the old world. The Africa of Timbuktu, and of Tunisia (The origin of the word Africa from Ifriqiya) were very much part of the old world. The idea of Asia, Europe, and Africa having separate identities is very recent. And arbitrary. The coast of the Mediterranean includes all three and has been mixing for thousands of years.
The Roman Province of Africa
By the time Caillie arrived in Timbuktu, it was a bit of a let down relative to the legends. The scholars had left when those less keen on learning had conquered Timbuktu in 1591 and it got swallowed into the Songhai empire. Learning can be lost with a little flame. See Alexandria. See Athens. See Great Zimbabwe. See the various ruins around the world. The secrets of Egypt disappeared almost completely till the 'discovery' of the Rosetta Stone started a process of relearning. It is also difficult for any one group to claim our shared learning. Learning is collaborative shoulders of giants stuff. Even if the giants are wanderers.