Title: Risālat Abī al-Rabīʻ Muḥammad ibn al-Layth ilá Qusṭanṭīn malik al-Rūm
Subjects: Early works to 1800, Relations, Ethnic relations, Islam, Christianity, Christianity and other religions
Places: Islamic Empire, Byzantine Empire
People: Constantine VI Emperor of the East (771-), Hārūn al-Rashīd Caliph (approximately 763-809)