Siege of Constantinople
860 CE.
Shown on the map at 41.000°, 28.900°.
The siege of Constantinople in 860 was the only major military expedition of the Rus' recorded in Byzantine and western European sources. The casus belli was the construction of the fortress Sarkel by Byzantine engineers, restricting the Rus' trade route along the Don River in favour of the Khazars. Accounts vary, with discrepancies between contemporary and later sources, and the outcome is unknown in detail. It is known from Byzantine sources that the Rus' caught Constantinople unprepared; preoccupied by the ongoing Arab–Byzantine wars, the empire was unable, at least initially, to make an effective response to the attack. After pillaging the suburbs of the Byzantine capital, the Rus' retreated for the day and continued their siege in the night after exhausting the Byzantine troops and causing disorganization. The event gave rise to a later Orthodox Christian tradition, which ascribed the deliverance of Constantinople to a miraculous intervention by the Theotokos.
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