Sviatoslav's invasion of Bulgaria

The Battle of Arcadiopolis, fought in March 970, was an engagement between Byzantine forces under Bardas Skleros and a Rus'-led coalition during Sviatoslav's invasion of Bulgaria. The Byzantine force, numbering between 10,000 and 12,000, faced an opposing force estimated at up to 30,000. Beyond the disparity in force sizes and the identities of the commanders, the primary sources do not provide sufficient detail to characterize the battle's operational or strategic consequences with confidence.

The Siege of Dorostolon was the decisive engagement of Sviatoslav's invasion of Bulgaria, pitting the Byzantine forces of John I Tzimiskes against Sviatoslav I of Kiev's Rus' army at the Danubian fortress of Silistra. The engagement resulted in a Byzantine victory and inflicted substantial casualties on the Kievan Rus', with recorded losses of 15,000 against a force assessed at 30,000. The two sides entered the siege at near numerical parity — the Byzantine force numbered between 28,000 and 30,000 — making the outcome a significant military defeat for Sviatoslav rather than merely an attrition of an outnumbered force. The battle effectively ended the Rus' presence in Bulgaria and secured Byzantine authority over the region, resolving the broader contest that had developed since Sviatoslav's initial entry into Bulgarian territory in 967.