Russia had demonstrated an expansionist policy in the Siberian Far East from the reign of Ivan the Terrible in the 16th century .

In the late 1550s , the ruler of one of the Kabardás , Temryuk ( or Temriuk ) , struck Attack a politico-military alliance with Tsar Ivan IV of Russia ( `` Ivan the Terrible '' ) , for mutual assistance against expansionist attacks Attack by the Persian and Ottoman Empires .

Polotsk had been captured Conquering and heavily fortified Cause_change_of_strength by the Russians under Ivan the Terrible in 1563 because the river Dwina , which led to Causation the key city of Riga , flowed Motion through it .