How much contact did Sub-Saharan Africa actually have with the rest of the world since the beginning of civilization?

Question

The book 'Guns, germs and steel' introduced me to the fact that the Sahara desert actually isolated Sub-Saharan Africa from the developments elsewhere since the beginning of civilization until European colonialism.

My main question: is this true? Were there major isolated exchanges of information? Is so, where? And why didn't it spread? This narrative seems very close to the racist, "savage, uncivilized" history espoused by European colonialist in the 18th and 19th century. It is a good assumption that factual historical research since the 1960's has changed this narrative that Jared somehow misses.

I guess it's a good idea to give a definition of civilization to begin with, so lets use the one from wikipedia: "a civilization contrasts with non-centralized tribal societies".
Additionally it's good to take dates into account, from wikipedia:

"The earliest emergence of civilizations is generally associated with the final stages of the Neolithic Revolution, culminating in the relatively rapid process of Urban Revolution and state formation, a political development associated with the appearance of a governing elite. The earlier neolithic technology and lifestyle was established first in the Middle East (for example at Göbekli Tepe, from about 9,130 BCE), and later in the Yangtze and Yellow river basins in China (for example the Pengtoushan culture from 7,500 BCE), and later spread. Similar pre-civilised "neolithic revolutions" also began independently from 7,000 BCE in such places as the Norte Chico civilization in Peru and Mesoamerica at the Balsas River. These were among the six civilizations worldwide that arose independently Mesopotamia is the site of the earliest developments of the Neolithic Revolution from around 10,000 BC, with civilisations developing from 6,500 years ago. This area has been identified as having "inspired some of the most important developments in human history including the invention of the wheel, the development of cursive script, Mathematics, Astronomy and Agriculture."

Answer 1

This thesis is manifestly false, and is indicative of the weaknesses of "Guns, germs and steel".

For example, the making of iron tools was probably passed up the Nile, to Kush and Meroe, and then across to East Africa; they were making iron tools well before 1000 AD; evidence of iron work by the Nok of Nigeria exists as earlier than 400 BC.

Nok culture - 1000 BC to 300 AD - Iron Age

There are other avenues of technology transfer at work in Africa: the trans-Saharan trade in salt and gold, between the sahel empires and Moroco, mediated by the Berbers.

Late medieval Sahel empires, based on trans-Saharan trade

Trade and the Spread of Islam in Africa is a later, non-European influence on Africa, in the Sahel, Sudan, and east Africa. Note that East Africa provides an entry to the eastern end of the Sahel, via the Sudan.

East African trade routes, with Arab and Indian contacts, 500-1000 AD.

Answer 2

The only historical connections that I know that exist starting with Ancient Greece and moving forward to the 18 hundreds are through Egypt pushing upriver (South) through the Nile and then through sporadic contact with the Romans (who were the Nubians for example?) After that you have the Portuguese and West Africa but even then I know of little contact until King Leopold II of Belgium and the famous "connection" by British exlorers made between the Nile and the Belgian Congo (that there was no connection but two entirely separate and massive River systems.) From what I have read of Belgian Colonial history there were no "River Civilizations" (though certainly people) along the breadth and depth of the Belgian Congo. This would mean a basically uninhabited region bigger in size than all of Western Europe being discovered in the late 1800's. That is not true today obviously.

Answer 3

First, Sub-Saharan Africa is an amazingly large territory and it would take ages to pinpoint all the contact points of each of its regions with the rest of the world. As a result, I will focus on the most documented set of contacts, which are contacts of Eastern Sub-Saharan Africa with the Mediterranean, through the Nile. Different cultures developed in what we know today as Sudan and Ethiopia, which were in contact with Egypt, and via Egypt, with the area around the Mediterranean sea. The biggest chunk of info comes, though from after 1,000 BC, when, eventually, the Nubians (Northern Sudanese) start interacting with the Classical world. For the way this happened, see a special series of article published in A&A journal, through the links below:

Sudan Archaeology from a Greco-Roman Perspective: Part 1, Part 2, Part 3, Part 4, Part 5