`Umar ibn al-Khattāb (in Arabic, عمر بن الخطاب) (c. 584 – November 7, 644), was an early Muslim convert from the Banu Adi clan of the Qurayshtribe, and a companion of Muhammad. He became the second Caliph (634 – 644) following the death of Abu Bakr, and is thus regarded by Sunni Muslims as one of the the Rashidun (four righteously guided Caliphs). Because of his conquests and political skills he is regarded as a pivotal figure in the history of Islam.
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