Rus' forces sailed into the Bosporus in a fleet of about 200 vessels and started pillaging the suburbs of Constantinople. Rus' Khaganate: Rus' Khaganate or Kaganate of Rus is a name applied by some modern historians to a hypothetical polity suggested to have existed during a poorly documented period in the history of Eastern Europe between c. 830 and the 890s. June 18, 860. Wiki link