Russian oligarchs (Russian: олигархи, romanized: oligarkhi) are business oligarchs of the former Soviet republics who rapidly accumulated wealth in the 1990s via the Russian privatisation that followed the dissolution of the Soviet Union. The failing Soviet state left the ownership of state assets contested, which allowed for informal deals with former Soviet officials as a means to acquire state property.
The Russian oligarchs emerged as business entrepreneurs under Mikhail Gorbachev (General Secretary, 1985–1991) using various loopholes during economic liberalization under Gorbachev's perestroika. Boris Berezovsky, a mathematician and former researcher, became the first well-known Russian business oligarch.