Articles:

• Wikipedia, “Kievan Rus’”, https://en.wikipedia.org/wiki/Kievan_Rus'

Videos:

• Crash Course, “Russia, the Kievan Rus and the Mongols”, https://www.youtube.com/watch?v=etmRI2_9Q_A&t=139s
• Epimetheus, “How the Rus became the Russians - Slavic history explained”, https://www.youtube.com/watch?v=U_2h16AYMMQ
• Geo History, “The origins of Russia”, https://www.youtube.com/watch?v=qUgzqkCW6A4
• Kings and Generals, “Slavs and vikings: Medieval Russia and the origins of Kievan Rus”, https://www.youtube.com/watch?v=W3CvfrmHpt4
• Useful Charts, “Rurikid dynasty family tree - Rurik the Viking to Ivan the Terrible”, https://www.youtube.com/watch?v=nByvWEGz8WA