section_path: History/First Bulgarian Empire
section_name: First Bulgarian Empire
paragraph_text: First Bulgarian Empire
  
  Not long after the Slavic incursion, Moesia was once again invaded, this time by the Bulgars under Khan Asparukh. Their horde was a remnant of Old Great Bulgaria, an extinct tribal confederacy situated north of the Black Sea in what is now Ukraine and southern Russia. Asparukh attacked Byzantine territories in Moesia and conquered the Slavic tribes there in 680. A peace treaty with the Byzantine Empire was signed in 681, marking the foundation of the First Bulgarian Empire. The minority Bulgars formed a close-knit ruling caste.
  
  Succeeding rulers strengthened the Bulgarian state throughout the 8th and 9th centuries. Krum introduced a written code of law and checked a major Byzantine incursion at the Battle of Pliska, in which Byzantine emperor Nicephorus I was killed. Boris I abolished paganism in favour of Eastern Orthodox Christianity in 864. The conversion was followed by a Byzantine recognition of the Bulgarian church and the adoption of the Cyrillic alphabet, developed in the capital, Preslav. The common language, religion and script strengthened central authority and gradually fused the Slavs and Bulgars into a unified people speaking a single Slavic language. A golden age began during the 34-year rule of Simeon the Great, who oversaw the largest territorial expansion of the state. The literature produced in Old Bulgarian soon spread north from Bulgaria and became the lingua franca of the Balkans and Eastern Europe. The political, cultural, and spiritual power of the Bulgarian Empire during the Krum's dynasty turned Bulgaria into one of the three superpowers in Europe at that time, alongside the Byzantine Empire and the Carolingian Empire of the Franks, which would later become the Holy Roman Empire.
  
  After Simeon's death, Bulgaria was weakened by wars with Magyars and Pechenegs and the spread of Bogomilism. Simeon's successor Peter I negotiated a favourable peace treaty. The Byzantines agreed to recognize him as Emperor of Bulgaria and the Bulgarian Orthodox Church as an independent Patriarchate, as well as to pay an annual tribute. The peace was reinforced with a marriage between Peter and Romanos's granddaughter Irene Lekapene. This agreement ushered in a period of 40 years of peaceful relations between the two powers. During the first years of his reign, Peter I faced revolts by two of his three brothers, John in 928 and Michael in 930, but both were quelled. During most of the reign of Emperor Peter I, the empire enjoyed a period of political consolidation, economic expansion, and cultural activity.
  
  Preslav was seized by the Byzantine army in 971 after consecutive Rus' and Byzantine invasions. The empire briefly recovered from the attacks under Samuil, but this ended when Byzantine emperor Basil II defeated the Bulgarian army at Klyuch in 1014. Samuil died shortly after the battle, and by 1018 the Byzantines had conquered the First Bulgarian Empire. After the conquest, Basil II prevented revolts by retaining the rule of local nobility, integrating them in Byzantine bureaucracy and aristocracy, and relieving their lands of the obligation to pay taxes in gold, allowing tax in kind instead. The Bulgarian Patriarchate was reduced to an archbishopric, but retained its autocephalous status and its dioceses.