Answer
The Battle of Dorostolon, fought in 971 near the Danube River, brought an end to John I Tzimiskes' campaign against the Rus'. This decisive battle resulted in a resounding victory for the Byzantine Empire, effectively repelling the Rus' invasion and reestablishing Byzantine dominance over the region. The battle's significance lies in its pivotal role in thwarting the Rus' expansion into the Balkans and consolidating Byzantine power in southeastern Europe.