Islamic extremist terrorism refers to acts of terrorism claimed by its supporters and practitioners to be in furtherance of the goals of Islam. The validity of an Islamic justification for these acts is contested by other Muslims. Islamic extremist violence is not synonymous with all terrorist activities committed by Muslims. Nationalists, separatists, and others in the Muslim world often derive inspiration from secular ideologies. These are not well described as either Islamic extremist or Islamist
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During Muhammad's lifetime, many in Mecca resented Islam and its followers. The Meccans started attacking Medina to destroy the Islamic state, but the Muslims successfully fended off the attacks. Muslims finally attacked Mecca under the leadership of Mohammad after eight years of Hijra and took control of the city.
In March of 624, Muhammad led some three hundred warriors in a raid on a Meccan merchant caravan. The Meccans successfully defended the caravan and then decided to teach the Medinans a lesson. They sent a small army against Medina. On March 15, 624 near a place called Badr, the Meccans and the Muslims clashed. Though outnumbered more than three times (one thousand to three hundred) in the battle, the Muslims met with success, killing at least forty-five Meccans and taking seventy prisoners for ransom; only fourteen Muslims died. This marked the real beginning of Muslim military achievement.
Muhammad turned to raiding caravans bound for Mecca. Caravan-raiding was an old Arabian tradition and according to Watt was "a kind of sport rather than war"and that the object of the raids was to take animals and other goods but killing was carefully avoided. Muslims justified the raids by the Meccans' confiscation of the property they had left at Mecca and the state of war deemed to exist between the Meccans and the Muslims.
Under Muhammad's immediate successors, the Islamic empire expanded into Palestine, Syria, Mesopotamia, Persia, Egypt, North Africa, and Iberia.