Multiple choice Which three empires were weaker or defeated at the time of the Arab expansion? The Persian, Roman and Byzantine empires The Persian, Roman and Celtic empires The Ottoman, Byzantine and Greek empires The American, Russian and German empires Reveal answer Fill a bubble to check yourself A Correct answer Explanation The rapid Arab expansion occurred while the Byzantine Empire was exhausted from wars with the Sassanid (Persian) Empire. These two powers were the primary empires weakened during this period.