'Oligarch' is probably a term you've heard mentioned before, specifically in reference to business leaders in Vladimir Putin's Russia who hold a great deal of political influence.

The term originates from the latinised Greek word 'oligarkhia' - meaning 'government by the few'. 

'Oligarchy' is a form of structure where the power lies with a small number of people.

In Russia the term applies to business leaders who rapidly accumulated wealth during the era of Russian privatisation as the Soviet Union came to an end in the 1990s.

Since Russia invaded Ukraine last week after months of tensions, there has been renewed interest in oligarchs, some of whom have been affected by sanctions levied at the country.Wirral Globe: Many oligarchs are close to Russian President Vladimir Putin (PA) Many oligarchs are close to Russian President Vladimir Putin (PA)

Who are the Russian oligarchs?

Some of the more well-known oligarchs include:

Alisher Usmanov - a metal magnate and early Facebook investor

Alexey Mordashov - the main shareholder and chairman of Severstal, a Russian conglomerate with interests in metal, energy and mining companies

Alexander Ponomarenko - chairman of the board of Russia’s largest airport Sheremetyevo International Airport 

Gennady Timchenko - a large stakeholder in several Russian raw materials companies

Mikhail Fridman - founder of Russia’s largest private bank Alfa Bank

Roman Abramovich - primary owner of a private investment company and owner of Chelsea FC

Petr Fradkov - head of Promsvyazbank and son of the former head of Russian foreign intelligence

Denis Bortnikov - deputy president of Russia’s second-biggest lender VTB and son of the FSB chief

Yury Slyusar - director of United Aircraft Corp

Elena Georgieva - chair of the board of Novikombank, a state-owned defence conglomerate

Which oligarchs have been sanctioned?

According to Forbes, in recent days billionaire oligarchs such as Fridman, Usmanov, Mordashov, Timchenko and Ponomarenko have all faced sanctions due to Russia's actions in invading Ukraine.

The billionaires named by the E.U. on Monday had previously evaded Western sanctions aside from Timchenko, who already faces sanctions from the United States and the UK.

All the previous names mentioned have either had their assets frozen or have been blacklisted from the UK.

In addition to that senior executives at state-owned banks such as Alexander Vedyakhin (Sberbank), Andrey Puchkov and Yuriy Soloviev (VTB) have been added to the US sanctions list.