Like many good ideas, the one to write the PhD thesis on which this book is based started over dinner. In 2005, the co-supervisor of my thesis, Roel Meijer, and I were at a restaurant discussing my intention to write a dissertation about radical Islam in the Middle East, but I was not entirely sure what to do yet. Roel, who was quite aware of my fascination with the dynamics of Islamist ideology, suggested I do something with Jihadi-Salafism. Although I do not recall his mentioning the name ‘Abu Muhammad al-Maqdisi’, of whom I had never heard at the time, I distinctly remember his saying: ‘Perhaps you should check out this website.’ The URL he suggested was, of course, www.tawhed.ws, al-Maqdisi's website and the biggest online library of Jihadi-Salafi literature. When I got home and found it, I was immediately struck by the huge number of sources available, and I just knew I had to do something with this site. This book is the product of the idea that was born that night.

My fascination with ideology and its development and flexibility is rooted in an inexplicable interest in beliefs and dogmas I have had for a long time. For years I have been intrigued by the intricate details of theological and ideological debates, whose participants often claim to be the only true followers of a certain tradition, all the while quoting the same books and scholars but coming up with entirely different practical solutions. This interest was, of course, directed towards Islamic and Islamist thought during my studies at university. In that sense, this book is something I had long wanted to write, probably even before I realised it myself.