It is known from Byzantine sources that the Rus' caught Constantinople unprepared, while the empire was preoccupied by the ongoing Arab–Byzantine wars and unable to deal with the Rus' threat. After pillaging the suburbs of the Byzantine capital, the Rus' retreated, although the nature of this withdrawal, and indeed which side was victorious, is subject to debate. The event gave rise to a later Orthodox Christian tradition, which ascribed the deliverance of Constantinople to a miraculous intervention by the Theotokos.