The document provides an overview of the civilizations that preceded and influenced the rise of Islam, including the Roman Empire, Byzantine Empire, and Sassanid Empire. It discusses the geographic reach and administrative structure of the Roman Empire. It then describes the split of the Christian church and the decline of the Western Roman Empire. The document outlines the history and influence of the Byzantine and Sassanid Empires, including their religious differences and ongoing conflicts. It notes that by the 7th century, the Byzantine, Sassanid, and emerging Arab civilizations were on a collision course.