Ideology 

This group has its own interpretation of Islam which is really very extreme. It believes in violence and those who do not comply with its beliefs or tend to disagree are seen as apostates (someone who has abandoned his/her religion). Its ideology can be traced back to the Ottoman Empire. It believes that it is responsible to restore the "Khalifat" or caliphate of Muslims which was there during the Ottoman rule.  The caliph is supposed to be the successor to Muhammad. It believes in worldwide capital punishment. It follows Saudi Wahhabi traditions and practices. It emphasizes on eschatology (a study on final assessment of humanity by God) and apocalypticism (a belief that the world will end soon). It is ready for a religious war and it believes that it will defeat Rome, Christianity to be precise, in the city of Dabiq, where Mahdi (a leader who will rule for many years before the Day of Judgement that is the final assessment) will take over and the prophecy would be fulfilled.