Trained as a Soviet mathematician, Boris Berezovsky made his money through navigating the wilds of Russia’s emergent market economy but found his true passion in the messy and opaque world of post-Communist politics.

With business interests including car dealing and banking, he was the most vocal among the oligarchs who rose to power in the 1990s on the back of rigged auctions of state companies.

The mixture of money and power earned Berezovsky, who has died at his UK home aged 67, the nickname “Godfather of the Kremlin”. That was the title both of a Forbes article and subsequent book by the American journalist Paul Khlebnikov, who faced an aggressive libel suit from Berezovksy in response and was murdered in 2004 in Moscow, though the perpetrators have never been identified.