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Succeeding the reign of Nikephoros II Phokas, John Tzimiskes ascended the throne as the Byzantine Emperor. Tzimiskes had a distinguished military career, earning renown for his victories against external adversaries. Notably, he led successful campaigns against the Kievan Rus', expanding the Byzantine Empire's influence in the region. Tzimiskes also focused on internal reforms, addressing administrative inefficiencies and corruption.