The Rightly-Guided Caliphs
With the death of Ali, the first and most notable phase in the history of Muslim peoples came to an end. All through this period it had been the Book of God and the practices of His Messenger - that is, thc Qur'an and the Sunnah - which had guided the leaders and the led, set the standards of their moral conduct and inspired their actions. It was the time when the ruler and the ruled, the rich and the poor, the powerful and the weak, were uniformly subject to the Divine Law. It was an epoch of freedom and equality, of God-consciousness and humility, of social justice which recognized no privileges, and of an impartial law which accepted no pressure groups or vested interests.
After Ali, Muawiya assumed the caliphate and thereafter the caliphate became hereditary, passing from one king to another.