Multiple choice What helped the Umayyad caliphs to expand their empire? The Byzantine and Persian empires were weak They used gunpowder the Sunnis and Shiites put away their differences They allied with the Franks Reveal answer Fill a bubble to check yourself A Correct answer Explanation The Umayyad caliphs benefited significantly from the exhaustion and internal decay of the neighboring Byzantine and Persian empires after their long wars against each other.