Whereas holy war is traditionally reduced to a legal category and a way of legitimatingacts of violence that disappeared with the modern schism between political andreligious institutions, this article proposes another view. In order to take the role ofreligion in holy war seriously, we should focus upon the effect of religion in theconduct of war, and the function which the use of religious violence fulfils in its socialcontext. In this respect, the impact of secularization has been shallow, and just likereligion in general, religious violence or holy war should rather be looked upon as asocial constant. Along with the privatization of faith, the public role of traditionalchurch religion was slowly taken over by civil religion: With the national cult asmedium, national war has been the modern expression of the social constant of holywar - an act of sanctification that can be understood only in religious terms.