Abu Bakr adopted the title of "Khalifat Rasul Allah", generally translated as "Successor to the Messenger of God". This was shortened to "Khalifa", from which the word "Caliph" arose. The use of this title continued with Abu Bakr's own successors, the caliphs Umar, Uthman and Ali, all of whom were non-hereditary. This was a group referred to by Sunnis as the Rashidun (rightly-guided) Caliphs, though only Ali is recognised by the Shia. Abu Bakr's argument that the caliphate should reside with the Quraysh was accepted by nearly all Muslims in later generations. However, after Ali's assassination in 661, this definition also allowed the rise of the Umayyads to the throne, who despite being members of the Quraysh, were generally late converts to Islam during Muhammad's lifetime.