a good part of Serbia, forcing Zaharija, who at the time was the Prince of Serbia, to flee to Croatia. Simeon of Bulgaria summoned all the Serbian dukes to pay homage to their new prince, but instead of instating Časlav, he took them all captive, annexing Serbia. Bulgaria considerably expanded its borders to the west, now neighbouring its powerful ally Michael of Zahumlje and Croatia, where Zaharija was exiled and soon died. Croatia at this time was ruled by the most powerful monarch in Croatian history, Tomislav. Reign Bulgarian rule (923-927) was not popular, and many Serbs fled to Croatia and Byzantium. After the death of Simeon (927) Časlav and four friends escaped to Serbia. Časlav found popular support and restored the state, and many exiles quickly returned. Servia reappeared only to fall ca. 960 under Byzantine and later under Bulgarian rule again. He immediately submitted to the overlordship of Byzantine emperor Romanos I Lekapenos and gained financial and diplomatic support for his efforts. He maintained close ties with Byzantium throughout his reign. Byzantine influence (the Church in particular) greatly increased in Serbia, as did Orthodox influence from Bulgaria. The period was crucial to the future Christian demonym (Orthodox versus Catholic) adopted by the Serbian Church, as ties formed in this era were to have great importance on how the different Slavic churches lined up when they eventually split during the Great Schism of 1054. Many scholars have felt that the Serbs, being in the middle of Roman and Orthodox jurisdiction, could have gone either way, but, unfortunately, information on this era and region is scarce. He enlarged Serbia, incorporating Travunia and parts of Bosnia while the borders of Časlav's state are unknown. He took over regions previously held by Michael of Zahumlje, who disappeared from the sources in 925. War with Magyars and death The Magyars had settled in the Carpathian basin in 895. Emperor Leo had employed the Magyars against the Bulgars in 894, during the Byzantine-Bulgarian Wars. In the years following, the Magyars mainly concentrated on the lands to the west of their realm. In 934 and 943 the Magyars raided far into the Balkans, deep into Byzantine Thrace. According to De Administrando Imperio, the Magyars, led by Kisa, invaded Bosnia, and Časlav hurried and encountered them at the banks of river Drina. The Magyars were decisively defeated, with Kisa being slain by Časlav's voivode Tihomir. In