Nevertheless, for at least six centuries Islam spread largely peacefully and gradually wherever there were trade connections with the wider Muslim world of the southern Mediterranean, the Persian Gulf and the Arabian Sea Islam spread from the Middle East to take hold across North Africa during the second half of the 7th century CE when the Umayyad Caliphate (661-750 CE) of Damascus conquered that area by military force. From there, it spread via Islamized Berbers (who had been variously coerced or enticed to convert) in the 8th century CE along the trade routes which crisscrossed West Africa, moving from the east coast into the interior of central Africa, finally reaching Lake Chad. Meanwhile, the religion also spread down through Egypt and swung westwards through the Sudan region below the Sahara Desert