Marriage between East and West?

As early as 781, Irene began to seek a closer relationship with the Carolingian dynasty and the Papacy in Rome. She negotiated a marriage between her son Constantine and Rotrude, a daughter of Charlemagne by his third wife Hildegard. During this time Charlemagne was at war with the Saxons, and would later become the new king of the Franks. Irene went as far as to send an official to instruct the Frankish princess in Greek; however, Irene herself broke off the engagement in 787, against her son's wishes.