Who was 'richest man in history' and what would be his net worth today?

Elon Musk, Jeff Bezos, Mukesh Ambani, not even Emperor Akbar I come close to the Mali Empire's late ruler, Mansa Musa who had "incomprehensible" wealth, according to the South China Morning Post.

The 14th century West African ruler's wealth was built on gold, salt and land and, according to historians, Musa was the richest person ever to walk the Earth.

So who was he exactly?

Mansa Musa, whose real name was Musa Kieta, was the ninth sultan of the West African kingdom, which was already considered very wealthy by the time he ascended.

He was born around 1280 AD into a family of rulers during the Keita Dynasty, and came into power in 1312 AD.

His wealth continued to skyrocket from mining salt and gold deposits and trading elephant ivory, as stated by National Geographic.

Musa, a devout Muslim, made the "most extravagant pilgrimage in human history" to Makkah from 1324-1325 AD, according to Magnates Media.

He left Mali with about 60,000 men and women, from royal officials to camel drivers and slaves, most of whom were reportedly decked in head-to-toe Persian silk and gold brocade.

Meanwhile, the 100 camels carried bags of pure gold.

Musa revitalised the cities in his kingdom and made architectural developments in the region in collaboration with Islamic scholars, whom he paid up to 200kg in gold for their efforts.

He built schools, libraries and mosques before he died in 1337 at age 57 and was succeeded by his sons, but eventually the empire fell apart.

Some estimates put Mansa’s modern day net worth at $400 billion to $500 billion, though it can be difficult to fairly calculate a fortune based on gold, salt and land.