Key ideas from Charlemagne

• Charlemagne actually proposed marriage to Byzantine Empress Irene around 800 CE, but the proposal was rejected by her advisers who then overthrew her
• In 782, Irene proposed betrothing Charlemagne's 7-year-old daughter Rotude to her son Constantine VI, but Charlemagne cancelled in 787 because he was too fond of his daughters
• The 811 Battle of Pliska resulted in Emperor Nicephorus's beheading by Bulgarian Khan Krum, who turned his skull into a drinking goblet
• Pope Leo III crowned Charlemagne Holy Roman Emperor in 800 after considering Irene's throne vacant due to her being female and having murdered her son
• Charlemagne's 46-year uninterrupted reign ended in 814 from pneumonia, with only one son Louis surviving to inherit the entire realm
• The alternate scenario explores how a successful Charlemagne-Irene marriage in 794 could have prevented the East-West Schism and fundamentally altered European religious history