Bulgaria in the late 9th and early 10th century (Петър Коледаров: "Схема на българските граници с Византия към 865 и 905 г. и с Хърватско през 30-те години на X в.") 10th-century military history of Croatia 920s conflicts 926 Battles involving the First Bulgarian Empire Battles involving medieval Croatia Military history of Bosnia and Herzegovina 10th century in Bulgaria Battles of the Middle Ages Medieval Bosnia and Herzegovina