Marriage Charter of Empress Theophanu

The Marriage Charter of Empress Theophanu (State Archives of Wolfenbüttel, 6 Urk 11) is the dower document for the Byzantine princess Theophanu. Written in Latin, the document was created in the Early Middle Ages after the marriage of Theophanu to Emperor Otto II in 972, which made her the Holy Roman Empress. The document was prepared by Otto II and exemplifies an instance of political and cultural contact between the Holy Roman Empire and the Byzantine Empire. It serves as an example of Ottonian Renaissance art, and the calligraphy of the manuscript has led it to be regarded as one of the most beautiful diplomatic documents of the Middle Ages.

After the fall of the Western Roman Empire, the Byzantine Empire was the sole successor of the Roman Empire. Charlemagne's imperial coronation in 800 put strain on Western relations with the Byzantine Empire ruled from Constantinople. When Otto I became emperor in February 962, there was contention between him and the Byzantine Empire, and this issue revived in 967 between Otto and Nikephoros II Phokas over the dominion of Italy. On 25 December 967, Pope John XIII anointed Otto II as Otto I's co-emperor.

...
Wikipedia