Comes from archaic Russian langauge- roughly translating into "formidable".
Ivan the Terrible is known in Russian as Ivan Grozny. Terrible being attached to him later, probably because he used to have his opponents and subjects raped to death, fed live to savage dogs or he had wild bears released into crowds of women and children.
Moving on, it is also the name of the capital city of the Russian region of Chechnya in the north Caucasus region of the
Russian Federation. A place of conflict for some two hundred years, two recent wars have ruined the country; where the Russian military, or the imported Islamic extremists ( Saudi born Amir Khattab- resonsible for attempted genocide in Dagestan) who lead the rebel movement do not have a monopoly on atrocities. Both sides are
locked in a futile and savage conflict. The people are kicked around like shit
in the middle.