Chernyakhovsk is a town in Oblast Kaliningrad, Russia. Originally called Wystruc (Polish), Isruties (Lithuanian) or Insterburg (German) and part of East Prussia, it was captured by the Soviet Union and renamed Chernyakhovsk.
Insterburg was founded by the Teutonic Knights as a castle in 1336. The settlement came into existence nearby, this settlement was also called Insterburg after the castle. Town privileges were given to the settlement on 10 October 1583.
In 1946 the town name was changed into Chernyakhovsk, after a Soviet general.
Following its takeover, the Soviet Union ousted all East Prussians and brought in Russians, Byelorussians and Ukrainians.