Dangantaka da Daular Rumawa ta tsananta bayan mutuwar matar Bitrus a tsakiyar shekarun 960.Mai nasara a kan Larabawa, Sarkin sarakuna Nikephoros II Phokas ya ki biyan harajin shekara-shekara ga Bulgaria a cikin 966, yana gunaguni game da kawancen Bulgaria tare da Magyars , kuma ya dauki nauyin nuna karfi a kan iyakar Bulgaria.An hana shi daga harin kai tsaye da aka kai wa Bulgaria, Nikephoros II ya aika da manzo zuwa ga yarima mai jiran gado na Rasha Sviatoslav Igorevich don shirya harin da Rasha ta kai wa Bulgaria daga arewa.Sviatoslav ya kaddamar da wani kamfen cikin hanzari da dakaru 60,000, ya fatattaki ‘yan Bulgarian a Danube, kuma ya ci su da yaki a kusa da Silistra, ya kwace wasu kagara 80 na Bulgaria a shekara ta 968. Rumawa sun karfafawa Sviatoslav sarkin Rasha ya kai wa Bulgaria hari, inda ya jagoranci kasar. don fatattakar sojojin Bulgaria da mamayar yankin arewaci da arewa maso gabashin kasar da sojojin Rasha suka yi tsawon shekaru biyu.