From the time of Muhammad, the final prophet of Islam, many Muslim states and empires have been involved in warfare. The concept of Jihad, the religious duty to struggle, has long been associated with struggles for promoting a religion, although some observers refer to such struggle as "the lesser jihad" by comparison with inner spiritual striving. Islamic jurisprudence on war differentiates between illegitimate and legitimate warfare and prescribes proper and improper conduct by combatants. Numerous conquest wars as well as armed anti-colonial military campaigns were waged as jihads.
