The richest man in history amassed a $400 billion fortune mining gold and salt in Africa

The people behind Celebrity Net Worth  has put together a list of the richest people throughout history after adjusting their fortunes for inflation.

CNW did not disclose the exact methodology used to ascertain the wealth of these men (there are no women on the list). Nor did they explain how you would convert the value of say, a stable full of horses in 1000 AD, into 2012 dollars.

But then again rigorous science is probably not the purpose of a site where the top story is about a rap star's new gold-chrome sports car.

At the top of the list is the little known historical figure Mansa Musa who ruled the empire of Mali which covered among others Ghana, Ivory Coast, Mauritania and Senegal in West Africa in the 14th century and included the famous trade city of Timbuktu.

Mansa Musa made his money in the gold and salt trade. According to CNW he controlled more than half of the world's supply of the commodities at the time. Mali and Ghana today are the continent's second and third largest producers of gold.

Here's the list of the 26 richest people of all time in 2012 dollars:

1. Mansa Musa, (ruler of Malian Empire, 1280-1337) $400 billion

2. The Rothschilds (banking dynasty, 1740- ) $350 billion

3. John D Rockefeller (oil monopoly, 1839-1937) $340 billion

4. Andrew Carnegie (steel magnate who sold his company to JP Morgan for $480 million in 1901, 1835-1919) $310 billion

5. Tsar Nicholas II of Russia (last Emperor of Russia, 1868-1918) $300 billion

6. Osman Ali Khan, Asaf Jah VII (last ruler of Hyderabad who loved gold and gems including the $95 million 184 carat Jacob Diamond which he reportedly used as a paperweight, 1886-1967) $236 billion

7. William the Conqueror (King of England, 1028-1087) $229.5 billion

8. Muammar Gaddafi (former Libyan leader said to have stashed away billions in overseas bank accounts, 1942-2011) $200 billion

9. Henry Ford (Ford Motor Company founder, 1863-1947) $199 billion

10. Cornelius Vanderbilt (industrialist, 1794-1877) $185 billion

11. Alan Rufus (given land for fighting alongside William the Conqueror, 1040-1093) $178.65 billion

12. Bill Gates (Founder of Microsoft – his peak net worth at the time of the dotcom bubble, 1955- ) $136 billion

13. William de Warenne, 1st Earl of Surrey (Norman nobleman given land after battle of Hastings, ??-1088) $146.13 billion

14. John Jacob Astor (businessman that started out in the fur trade, 1864-1912) $121 billion

15. Richard Fitzalan, 10th Earl of Arundel (English nobleman, 1306-1376) $118.6 billion

16. John of Gaunt (son of Edward III, 1330-1399) $110 billion

17. Stephen Girard (shipping and banking mogul, died without heirs 1750-1831) $105 billion

18. Alexander Turney Stewart (Dept Store entrepreneur, 1803-1876) $90 billion

19. Henry, 1st Duke of Lancaster (English nobleman, 1310-1361) $85.1 billion

20. Friedrich Weyerhaeuser (used his timber wealth to become largest private landowner in America, 1834-1914) $80 billion

21. Jay Gould (railroad tycoon, 1836-1892) $71 billion

22. Carlos Slim (Mexican cellphone magnate, 1940- ) $68 billion

23. Stephen Van Rensselaer (one of America's top land owners including Manhattan Island, 1764-1839) $68 billion

24. Marshall Field (Chicago retailer and real estate mogul, 1834-1906) $66 billion

25. Sam Walton (Walmart founder, 1918-1992) $65 billion

26. Warren Buffett (investor, 1930- ) $64 billion

Click here to see CNW's slide show.

Image is from Wikimedia Commons. Mansa Musa depicted holding a gold nugget, from the 1375 Catalan Atlas. The inscription reads: This Negro lord is called Musa Mali, Lord of the Negroes of Guinea. So abundant is the gold which is found in his country that he is the richest and most noble king in all the land