Umar Ibn Khattab

Dates:
Born: c. 586 in Mecca, Arabia
Died: November 3, 644 (23 AH) in Medina, Arabia (assassinated)
Conversion to Islam: 618
Caliph: 634 - 644

Definition:
Umar was the second successor, or caliph, to Muhammad, but he was also Muhammad's father-in-law. Umar is sometimes referred to as the "St. Paul" of Islam, first because of his success in spreading Islam and second because he was originally opposed to Islam, but had a conversion experience which caused him to reverse course and support Muhammad.

Umar was a member of the Umayyah clan of the Meccan Quraysh tribe - thus then name of the empire he founded, the Umayyad Empire. He had opposed Islam and Muhammad and, when he heard that his sister and her husband had converted, he went to admonish them. According to tradition, though, he allowed them to recite verses from the Quran for him and converted on the spot.

After the death of Muhammad, Umar made sure that the leadership of the community went to Abu Bakr, an effort which helped ensure that the group was not split according to differing loyalties between those who were from Mecca and those from Medina. Abu Bakr in turn designated Umar as his successor when he was on his deathbed. Umar was the one who determined that the year of the Hijra would be the first year of a new Islamic calendar and he organized the expanding territories conquered by Muslim forces.

Indeed, it was under Umar's leadership that Islam made its largest and fastest expansion. During his reign Muslim forces conquered Syria, Jerusalem, Egypt, Libya, Iraq, and the armies of Persia. One ingenious means for ensuring the continued expansion of Islam was Umar's decision to forbid Arabs from owning any land. Thus excluded from this way of developing wealth, they were motivated to continue fighting and conquering.

When Muslims look back upon a Golden Age of Islam, this is usually the era they have in mind - this is when Islam was making its biggest gains, when it was most feared and when Muslims were first at the top of the pecking order in their region of the world. It is also when Islam was, in some ways, it's most "pure," not yet affected seriously affected by the corruption of power and privilege.