When Hazrat Umar went to the mosque to lead a prayer, a Magian named Abu Lulu Feroze, who had a grudge against Hazrat Umar on a personal matter, attacked him with a dagger and stabbed him several times. Hazrat Umar reeled and fell to the ground.
When he learned that the assassin was a Magian, he said, "Thank God he is not a Muslim."
The injuries were so serious that the great Khalifa died the next morning. Full biography of the great Caliph:http://baharemadinah.com/index.php?option=com_content&view=article&id=137:hazrat-umar-farooq&catid=47:the-blessed-companions&Itemid=350
Abu lulu feroze
The first Caliph was Abu Bakr Assidik.
A caliph
The last Caliph died in Turkey in 1936, but he was not killed. He was merely deposed without a successor.
Caliph meaning the representative of God on earth
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
He was the third Caliph after Muhammad's death, and was killed by the Umayyads.
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
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.