Which of the following contributed to the rapid expansion of the Islamic/Arab Empire in the century following the death of Muhammad? The weakened condition of the Byzantine and Persian empires A smooth succession of caliphs selected by election The violent campaigns against infidels The uniting of all Arab's behind Muhammad's relative Ali

Option: The weakened condition of the Byzantine and Persian empires.

Explanation:

With the new religious zeal, the Arab armies move forward to spread Islam. Arabs invasion in the lands of the older empires led in the founding of one of the largest empire called the Arab Empire. The early expansion of the Empire was to conquer the lands of unbelievers of Islam and to convert them. The Empire ruled by the successors of Mohammed called themselves Caliphate. Wining the wars of crusades in the land of the Byzantine Empire, led the Arabs to spread their empire in Europe. The Muslim conquest in Persia resulted in the fall of the Sasanian Empire and the Zoroastrian religion.