He was not killed by a single person. he was killed by a large group of Muslims together. after some times of starting his power he became a coppupted King. he took his relatives in governmental positions and he was eating too much and... so people hated him and finally killed him toghether. then people asked Imam Ali a.s. to get power so Talha and Zubair and Aisha who wished to get power accused Ali a.s. for killing of Uthman to use this as an excuse to fight Ali a.s. and get power. so they made the Camel war against Ali a.s.
The first four Caliphs were called the Rightly-Guided Caliphs. After that, the dominant Caliph-line followed the Umayyads, the Abbassids, the Seljuks, and finally the Ottomans. The Fifth Caliph was the First Umayyad Caliph: Mu'awiya I.
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The fifth orthodox Caliph is the Caliph Omar Ibn Abd El Aziz
The first main 4 Caliphs (who are called the 4 orthodox caliphs) are:HAZRAT ABU BAKR SIDDIQUE (Raddi Allah Unho)The First Caliph of IslamHAZRAT UMAR FAROOQ (Raddi Allah Unho)The Second Caliph of IslamHAZRAT USMAN GHANI (Raddi Allah Unho)The Third Caliph of IslamHAZRAT ALI MURTZA (Raddi Allah Unho)The Fourth Caliph of Islam
The first Caliph was Abu Bakr Assidik.
The fourth Caliph was Ali ibn Abi Talib (Radi Allahu Anhu).
A caliph
Caliph meaning the representative of God on earth
Ali son of Abu Talib. Ali was the cousin of Prophet Muhammad and later became his son-in-law. He later became the fourth caliph of Islam.
SUNNI ISLAM believed that any Muslim could become Caliph if he was a good community leader; heredity was not terribly important.
Hadhrat Mirza Masroor Ahmad is a Caliph (Khalifa). He is the current Caliph for the Ahmadiyyah Movement of Islam
Abu lulu feroze
There used to be a central authority for Sunna Islam - the largest branch of Islam. That was called the Caliph. However, for almost a century now, there is no such central authority.
He is Omar Ibn Al-Khattab (May God be pleased with him).
their duties were to expand Islam to do this they used well trained armies