This paper tests three main theses by the French political scientist Olivier Roy concerning the social integration of Islamic neofundamentalists in Europe. Firstly, Roy assumes that Islamic neofundamentalists have a strong global identity, but only a weak national identity and are therefore uprooted. Secondly, Roy expects Islamic neofundamentalists to live segregated from the majority society and avoid respective contact. Thirdly, Roy presumes that Islamic neofundamentalists feel discriminated against. We test these assumptions with data based on a survey on different patterns of Muslim religiosity. The study was conducted in 2009 among Muslims in selected cities in North-Rhino Westphalia containing an oversample of highly religious Muslims (N=228). As a first step, we measure Islamic neofundamentalism by means of agreement with the main religious tenets. As a second step, we analyze the association of Islamic neofundamentalism with uprootedness, segregation and perceived discrimination.