When Pepin the Short died, the Frankish kingdom passed down the Carolingian line to Charles and his younger brother, Carloman. In 771, Carloman fell sick and died, and Charles seized control over his lands as well. Charles the Great, aka Charlemagne, proved proficient on the battlefield. Beginning in 773, he conquered the Lombards, Saxons, Arabs and Avars; on today's map, his kingdom would encompass France, Belgium, Holland, Switzerland, Austria and parts of Germany, Italy, Croatia, the Czech Republic, Slovakia, Hungary and Spain [source: Barbero and Cameron].
To the rulers of the Byzantine Empire, Charlemagne's growing kingdom was merely a patchwork of barbaric clans. However, the early Middle Ages king promoted literacy and education among his subjects. Dubbed the Carolingian Renaissance, Charlemagne patronized education and art to an extent unparalleled in medieval Europe. He began with the court schools, where students and scholars could engage in self-directed study [source: Colish]. Along with the secular institutions, the king also revived ecumenical (religious) schools. Architectural projects accompanied the cultural resurgence, with 16 monasteries and more than 230 cathedrals either built or renovated during Charlemagne's reign [source: Stalley].
Charlemagne also sought to unify the Frankish kingdom under the Christian faith and root out corruption in the clergy. He established Latin, the language of the Roman Catholic Church, as the official tongue. The Byzantine Empire, in contrast, spoke Greek. Believing in the educational power of the public Christian services, or liturgy, Charlemagne attempted to standardize them across the kingdom [source: Colish].
Relations between the church and Byzantium (whose ruler still held the honorary title of Roman Emperor) began to splinter in 726 when Emperor Leo III launched a campaign against iconoclasm, or religious icons. Wishing to prevent idol worship, Leo's decree outlawed Christian symbols, such as crucifixes. The final straw came toward the end of the eighth century when Emperor Constantine VI's mother, Irene, disowned and blinded her son and claimed the imperial title for herself. Balking at the notion of a female emperor, the church council resolved to coronate Charlemagne and split definitively from the Byzantine Empire.