Since 2013 the number of black billionaires has increased by two, according to Forbes’ billionaire list. So how did these black people become so wealthy? This certainly just didn’t happen overnight.

Let’s take a look at the World’s Richest Black People:

10) Tony Elumelu – $1 Billion

Africa’s revered business leader Tony Elumelu has a controlling interest in Transcorp, Nigeria’s largest publicly-traded conglomerate; a significant stake in the United Bank of Africa; and an extensive portfolio of real estate across Nigeria.

9) Mo Ibrahim – Net worth: $1.1 billion (British)

Source of wealth: Mobile and Telecommunications
Born Mohammed Ibrahim best known as Mo Ibrahim, he made his first big deal when he sold Celtel for $3.4 billion back in 2005. This Company was one of the first to serve Africa and the Middle East mobile. In the year 2007 he founded Mo Ibrahim Foundation, which fights corrupt leadership in Africa. This foundation offers a lifetime award that amount to $5 million and it is given over a period of 10 years to the retired African leaders whose leadership was seen as transparent. The foundation also publishes the Ibrahim Index of African Governance by their ability to ensure sustained economic opportunities and the rule of law. He is also the founding member of Satya Capital that’s worth more than $20 million.

8. Theophilus Danjuma – Net Worth: $1.1 billion (Nigerian)

The self made Nigerian billionaire resides in Abuja. He is a retired Nigerian general. He served as the defense minister of Nigeria. He is the chairman of South Atlantic Petroleum.

7) Folorunsho Alakija – Net worth: $1.9 billion (Nigerian)

Source of wealth: Fashion and Oil
The first female billionaire from Nigeria, Folorunsho Alakija made her billions from oil and fashion. She started her business in the 70s after she left her day job as a secretary to focused on her studies in fashion in England. Upon her return to Nigeria she founded Supreme Stitches, that catered fashion for women of high society. She is also the founder of Famfa oil, a company that owns substantial participating interest in OML 127, a lucrative oil block on the Agbami deep water oilfield.

6) Patrice Motsepe – Net worth $2.1 billion (South African)

Source of wealth: Mining
Raised in very poor rural area, Patrice Motsepe is the first and only black South African billionaire. He is the founder of African Rainbow Minerals (ARM); a Stock Exchange-listed company in Johannesburg. The interest of the company include platinum, nickel, chrome, copper, iron, gold and manganese. He also holds a stake in Sanlam, which is a publicly traded financial service company. In February 2013, Motsepe reported that he will be giving away half of his income to charity. He has benefited from South Africa’s Black Economic Empowerment laws, which states that companies should be at least 26% black-owned in order to get a government mining license.

5) Oprah Winfrey – Net worth: $3 billion (American)

Source of wealth: Media
Oprah Winfrey is the richest African American. The majority of her net worth was generated from her 25 year profitable daytime TV show and earnings from her Harpo production company, which she helped celebrities like Dr Phil, Dr Oz as well as Rachel Ray. She continues to support educational courses and has spent a whopping $100 million to build the Oprah Winfrey Learning Academy for girls in Johannesburg, South Africa.

4) Isabel dos Santos – Net worth: $3.3 billion (Angolan)

Source of wealth: Investments
The daughter of Angola’s president, José Eduardo dos Santos and the current richest woman in Africa. Isabel is a very successful investor; her investments include 25% stake in the Angolian mobile phone company Unitel and 25% stake in Angolian bank Banco Bic SA. She also has a few other investments which make her net worth to more than $3 billion. She is currently the richest black woman and richest woman in Africa.

3) Mike Adenuga – Net worth: $4 billion (Nigerian)

Source of wealth: Oil and Telecoms
Mike Adenuga is the founder of Globacom, Nigeria’s second largest mobile phone network which has about 24 million subscribers. Adenuga also owns Coinciol Producing; this company was one of the first Nigerian companies to have an oil license in the early 90’s. He started making his fortune at the age of 26, when he returned to his home town after studying in the U.S.