Originally a ducal family from Saxony, the Ottonians (named after their first king Otto I the Great) seized power after the collapse of Carolingian rule in Europe and re-established the Holy Roman Empire. Ottonian architecture first developed during the reign of Otto the Great (936 - 975 C.E.) and lasted until the mid-11th century. Surviving examples of this style of architecture are found today in Germany and Belgium.
Ottonian architecture chiefly drew its inspiration from both Carolingian and Byzantine architecture and represents the absorption of classical Mediterranean and Christian architectural forms with Germanic styles. In some of its features, it foreshadowed the development of Romanesque architecture which emerged in the mid-11th century. It is remarkable for its balance and mathematical harmony--a true reflection of the high regard in which the Ottonians held the mathematical sciences.
Barring a few examples that were influenced by the octagonal Palatine Chapel built by Charlemagne in Aachen, Ottonian religious architecture tends to diverge from the model of the central-plan church, drawing inspiration instead from the Roman basilica, which typically consisted of a long central nave with an aisle at each side and an apse at one end. The Ottonians adopted the Carolingian double-ended variation on the Roman basilica, featuring apses at both ends of the church rather than merely one.
One of the finest surviving examples of Ottonian architecture is St. Cyriakus Church in Gernrode, Germany, constructed between 960-965. The central body of the church has the nave with two aisles sided by two towers characteristic of Carolingian architecture, but it also displays novelties anticipating Romanesque architecture, including the alternation of pillars and columns (a common feature in later Saxon churches), semi-blind arcades in galleries on the nave, and column capitals decorated with stylized leaves of acanthus and human heads .