[German version]

(Umar b. al-Ḫaṭṭāb). Second of the four 'rightly-guided' caliphs (AD 634-644). O. established the foundation of the Islamic empire and its political institutions through expansion as well as domestic organization. His negative and reserved attitude toward Jews and Christians was reflected in a number of religious-law and political decisions. The Sunnites revere O. even today as an ideal Muslim and just ruler, while the Shiites despise him as an advocate of Abu Bakr and hence an enemy of Ali in the prophet's line of succession. O. established the Islamic ca…