text: In the Novgorod First Chronicle, it was not Oleg, but Igor who initiated the actions: telling Askold that he, unlike Igor himself, was not a prince or of a princely clan, Igor and his soldiers killed Askold and Dir, and then Igor rather than Oleg became prince in Kiev. There is also no mention of Kiev being proclaimed as the "mother of Rus' cities". Igor went on to impose tributes on various tribes, and brought himself a wife named Olga from Pleskov (Pskov), with whom he had a son called Sviatoslav. Ostrowski (2018) noted that this is rather different from the narrative in the Primary Chronicle, where Oleg is in charge while Igor is passive and not mentioned again until 23 later: "As Igor’ grew up, he followed after Oleg, and obeyed his instructions", and Olga "was brought to him from Pskov" to be his bride. In the subsequent Rusʹ–Byzantine War (907) (absent in Byzantine sources), the Novgorod First Chronicle again narrates that it was Igor leading the attack ( "Prince Igor went against the Greeks with thousands of Rus' warriors."), yet the Primary Chronicle once more claims: "Oleg went against the Greeks, leaving Igor’ in Kiev."
  Al-Masudi
  The only foreign source to mention one of the co-rulers is the Arab historian Al-Masudi. According to him, "king al-Dir [Dayr] was the first among the kings of the Slavs." Although some scholars have tried to prove that "al-Dir" refers to a Slavic ruler and Dir's contemporary, this speculation is questionable and it is at least equally probable that "al-Dir" and Dir were the same person. Following his works, historians believe that Dir ruled after Askold, mainly in the 870—880s. In that case, on entering Kyiv, Oleg's soldiers killed just Dir while Askold had died earlier.
  Facts and records
  The Rus' attack on Constantinople in June 860 took the Greeks by surprise, "like a thunderbolt from heaven," as it was put by Patriarch Photios in his famous oration written for the occasion. Although the Slavonic chronicles tend to associate this expedition with the names of Askold and Dir (and to date it to 866), the connection remains tenuous. Despite Photius' own assertion that he sent a bishop to the land of Rus' which became Christianized and friendly to Byzantium, most historians discard the idea of Askold's subsequent conversion as apocryphal.