The great medieval empire of the Kievan Rus covered the territories of present-day European Russia, Belarus and Ukraine. This map shows the influence of the Byzantine Empire on the settlement region of the Kievan Rus.
Kievan Rus, 11th century, map, 2006, copyright: Captain Blood, Britta Müller-Schauenburg, image source: Wikimedia Commons, https://commons.wikimedia.org/wiki/File:Kievan_Rus_en.jpg?, Creative Commons License Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0 DEED), https://creativecommons.org/licenses/by-sa/3.0/.