Routinely, people who have over the past five years travelled to Western Asia are being referred to as “foreign fighters”. Though, admittedly, many among them did join various armed groups, a fairly significant number of them did not or even could not become fighters. This is true first of all for children who travelled with their parents as well as for young females, who in the West pejoratively are called “jihadi brides”. However, even these categories aside, the (young) men who did join armed groups in Syria and Iraq, though they may be identified as “fighters”, may also not be regarded (and certainly many among them do not see themselves) as “foreign”. For the overwhelming number of people who travelled to West Asia and joined the Islamic State, their status in the entity is more like naturalized citizens whose naturalization process is epitomized by the joining of the armed forces of the Islamic State. Those who did not (or could not) join the IS armed forces became citizens by pledging allegiance to khilafa and by performing what they themselves regard as compulsory hijra – relocation from the lands of unbelievers to the land of Islam under the declared khilafa. The khilafa project initiated by the Islamic State is a unique phenomenon not only from the point of view of the theories of international relations but also with respect to classical notions of state formation and nation-building, and it puts the conceptualization of citizenship in a new light.