Battle in Dalmatia

A very long and difficult war began between the Bulgarian tsar Simeon I and the Byzantine emperor Romanos I Lekapenos, who wanted to take over the Byzantine Empire. Under intense Bulgarian pressure and suffering defeat after defeat, Byzantium began negotiations with Serbia and Croatia to create an alliance against the Bulgarians. Informed of these plans by Prince Michael Višević of Zachlumia, who had been forced to retreat to the islands after Serbian rulers seized most of his lands, Simeon conquered Serbia in 924. Through deception, he destroyed its aristocracy and incorporated the country directly into the Bulgarian Empire.

The Serbian ruler Zaharija Pribislavljević went into exile at the Croatian court, while huge waves of Serbian refugees entered Croatia after the destruction of their kingdom. Seeking to bring Croatia into a coalition, Romanos I ordered the province of Dalmatia in 925 to pay its dues to the Croatian state rather than Byzantium. The Dalmatian territories, including most towns and northern islands, consequently became King Tomislav's property and remained in Croatia. The Serbs of Zachlumia, allied with Croatia and Prince Michael, became Tomislav's vassals before 926. Tsar Simeon sent an army led by an alogobotur to drive the Serbian refugees farther into Croatia.

War broke out in 926.