If you Gurgled the name you know what his role in the early years of the Communist repression of Russia was. For those who haven't, "Iron Felix" was the Bolshevik founder of the Soviet secret police, first known as Cheka and later as the OGPU, ultimately the KGB.
Not exactly obscure. He carried out the "Red Terror" to destroy all opposition to Lenin, (which was much more than most people know). No-one knows how many people were summarily executed, but it was well over a million. Simultaneously he commanded the Bolshevik genocide against the Cossacks.
This is the guy that Putin is putting back on a pedestal in front of the KGB (now SVR) building in Moscow. A mass murderer. Nice.
Totally obscure. Get back in your time machine and dial it to sometime between 1917 and 1987. Nobody wants you here.