How powerful was the Malian empire?

According to Wikipedia:

Mansa Musa Keita came to the throne through a practice of appointing a deputy when a king goes on his pilgrimage to Mecca or some other endeavor, and later naming the deputy as heir. According to primary sources, Musa was appointed deputy of Abubakari Keita II, the king before him, who had reportedly embarked on an expedition to explore the limits of the Atlantic Ocean, and never returned. The Arab-Egyptian scholar Al-Umari[16] quotes Mansa Musa as follows:

The ruler who preceded me did not believe that it was impossible to reach the extremity of the ocean that encircles the earth (meaning Atlantic), and wanted to reach that (end) and obstinately persisted in the design. So he equipped two hundred boats full of men, as many others full of gold, water and victuals sufficient enough for several years. He ordered the chief (admiral) not to return until they had reached the extremity of the ocean, or if they had exhausted the provisions and the water. They set out. Their absence extended over a long period, and, at last, only one boat returned. On our questioning, the captain said: 'Prince, we have navigated for a long time, until we saw in the midst of the ocean as if a big river was flowing violently. My boat was the last one; others were ahead of me. As soon as any of them reached this place, it drowned in the whirlpool and never came out. I sailed backwards to escape this current.' But the Sultan would not believe him. He ordered two thousand boats to be equipped for him and for his men, and one thousand more for water and victuals. Then he conferred on me the regency during his absence, and departed with his men on the ocean trip, never to return nor to give a sign of life.[17]

https://en.wikipedia.org/wiki/Musa_I_of_Mali1

https://en.wikipedia.org/wiki/Abu_Bakr_II2

So there is at least one 14th century source claiming that the previous Mansa, Abubakari Keita II, set out in a fleet of boats to cross the ocean and didn't return. But how far Abubakari Keita II's fleet traveled, in which direction, and what they may have discovered, has been a mystery for about 706 years by 2018.

If Abubakari Keita II's fleet had 2,000 boats, and 1,000 more boats full of supplies, and if the average boat had between 1 and 100 crewmen, there would have been between 3,000 and 300,000 men in his fleet. And even if the fleet was much smaller and had much fewer men than stated, there could be hundreds of different stories about the experiences of various persons in the fleet - if only we knew those stories.

Mansa Musa is a well acknowledged historical figure, ruler of an empire well endowed with precious metals at a time when Europe was denuded of those in consequence of a two millennia long trade deficit with the far east.

Historical estimates of this type are always approximates, but Mansa Musa's estimated wealth is so far ahead of second place that an estimate of him as the richest person in the historical record seems accurate.

POWER AND EXTENT OF THE MALI EMPIRE

At its peak during the 14th century, the Mali empire controlled an area of well over one million Km² (approx. three times the size of modern Germany):

At its height, under the reigns of Mansa Musa I and Mansa Sulaymän, the Mali empire covered the entire Sudan-Sahel region of West Africa. Many peoples and cultures were thus brought together under a single political head.

Source: D. T. Niane, 'Mali and the second Mandingo expansion' in the UNESCO 'General History of Africa, vol. 4'

"The Medieval Mali Empire at the end of Mansa Musa's reign (1337 CE)". Attribution

Although the region this area covers has been mostly very poor for the last couple of centuries, in the 14th century and earlier the climate was milder and there was plenty of pastureland. Even in the 16th century when the empire had been in decline for at least a century, Mali was described by the scholar Mahmud Ka'ti as having

"some 400 towns and its soil is most fertile. Among the kingdoms of the rulers of the world, only Syria is more beautiful. Its inhabitants are rich and live comfortably."

Source: Niane

The Moroccan explorer and scholar Ibn Battuta also emphasizes the abundance of food. Niane also adds:

...an estimate that the population of Mali was some 40-50 million. The river valleys of the Niger and the Senegal were virtually human anthills. The capital, Niani, had at least 100 000 inhabitants in the fourteenth century

Information provided by Leo Africanus allows us to estimate that Niani's population was still substantial (at least 60,000) at a time (early 16th century) when it had been in decline for sometime. The empire's source of wealth was quite diverse: tributes, trade, mining (especially gold) and agriculture, the last mentioned employing most of the population. Food was abundant and this agricultural wealth made it possible to support a large army:

The standing army, which included both infantry and cavalry units, numbered more than 100,000 men at the height of the polity.

Source: Alice Willard, 'Gold, Islam and Camels: The Transformative Effects of Trade and Ideology'. In 'Comparative Civilizations Review, Vol. 28 (1993), No. 28'.

Mali was the largest producer of gold in the world at the time and also had large resources of copper. Salt and cotton were traded with the forest regions to the south (modern day Ghana and Ivory Coast) for yet more gold, as well as the very substantial kola nut trade, and palm oil. The gold, along with slaves and ivory, was sent in caravans across the Sahara (both north and east) in exchange for a variety of items including salt, clothing, iron and Arabian horses for the Malian army's cavalry. The caravans which transported these goods were sometimes enormous (even allowing for some exaggeration), numbering

...more than 12,000 camels. This, by no means among the largest of the caravans (some of which were reported to have more than 100,000 camels...)

Source: Willard

When Musa I annexed Timbuktu in 1324, he and his successors turned it into a cultural centre as well as a major commercial hub for the trade routes across the Sahara, literally putting it on the map (see the Catalan Atlas of 1375 below). Musa also brought with him the Andalusian architect Abu Es Haq es Saheli to construct palaces and mosques in Timbuktu and elsewhere. Timbuktu also became a centre of learning, housing the largest library in Africa since the Library of Alexandria.

MUSA I's WEALTH

How wealthy was Mansa Musa I? He probably ranks among the wealthiest men in history, but modern estimates (unsurprisingly) don't really agree (see here and here, for example). Famed for his wealth in Roman times, Marcus Licinius Crassus' fortune (max. $20 billion according to this estimate) may well have been mere pocket money compared to Musa's modern estimate of $400 billion. Musa was wealthy enough to disrupt the Egyptian economy by spending and giving away huge amounts of gold when he stopped in Cairo on his way to Mecca.

Mansa Musa distributed so much gold as gifts, and the Malians spent such large amounts in the market, that gold declined in value and did not recover for several years.

Source: David Conrad, Empires of Medieval West Africa

Whether he is richest person ever, as claimed here, is surely impossible to determine with certainty, and what is often omitted from online sources (here and here, for example) is that

By the time Mansa Musa was ready to return to Mali, he had used up all his gold, so to get home he had to borrow money at an exorbitant rate of interest.

Source: Conrad

Section of the 1375 Catalan Atlas showing Mansa Musa (bottom, with gold crown - click image to enlarge).

DID MUSA's PREDECESSOR REACH THE AMERICAS BEFORE COLUMBUS?

The short answer is that this is unproven.

The interpretion of the evidence for this is controversial at best. The story that Musa's predecessor Abu Bakr II went off in search of 'the edge of the Atlantic Ocean' with a large fleet comes from a single source, the Arab historian Shihab al-Umari. Even if we choose to accept this story, this by itself is obviously not evidence that Abu Bakr II actually reached the Americas.

The arguments presented in Ivan van Sertima's book They came before Columbus are not accepted by mainstream historians, and Mesoamerican academics have been especially critical. This review by Ronald W. Davis in The International Journal of African Historical Studies is pretty scathing:

his work is a strenuous attempt to extend the boundaries of absurdity in a genre which has never attracted much rigorous scholarship in the best of times...its content and format raise questions about the motivations of everyone involved, from the author to his publishers, in marketing a relatively expensive, useless publication.

The Welsh archaeologist Glyn Daniel was just as critical, describing Sertima's work as "ignorant rubbish" and "badly argued theories based on fantasies" West African historian Djibril Tamsir Niane is less scathing but also does not accept Sertima has proved his case:

Ivan Sertima, an Afro-American researcher, has a theory that blacks were the first to sail to America. He has analysed minutely Mexican and Central American civilizations and finds Mandingo elements in these cultures. The theory is enticing, but unproved.

There are a number of reviews on the internet, including this anonymous one which are very positive, but none seem to be by well-known academics.

Based on having read about 60 pages of 'They came before Columbus', there do seem to be some obviously misleading and / or false statements. For example, the author claims that the Mali empire was bigger than the Roman empire. In another section, he mentions 'Three Mulattoes of Esmeralda', saying they were the descendants of 17 Africans shipwrecked on the South American coast; all this is basically true, but it is also irrelevant as he omits to mention that the 17 Africans were actually 23 Africans (17 slaves plus 6 free men) who were shipwrecked in 1553.

One of the main arguments for an early African presence in the Americas concerns the 'obviously' negroid features of Olmec statues, the main thing cited being the broad noses on the statues. However, broad noses have more to do with climate than race: people from arid / dry regions tend have longer, narrow noses (moistening the dry inhaled air requires a larger mucuous area) whilst those from tropical regions across the world (Africa, South America, Asia) have broader noses. The article Robbing Native American Cultures (pdf) provides a comprehensive critique of Sertima's work.

Concerning the guanín-tipped spears, these were indeed sent back to Spain by Columbus and tested, and the results were as stated. However, the use of the alloy guanín in the Americas dates back to at least the 1st century AD, some 1200 or more years before the supposed arrival of Abu Bakr II and his fleet.

Additional source:

The Cambridge History of Africa, vol. 3