The purpose and aim of this research was to analyze if Lewis R. Rambos conversion the- ory can be applied to describe religious radicalization towards violent Islamic terrorism or not. The research has analyzed and investigated if there are any differences or similarities, regarding risk factors and existential dimensions before the attacks of three terrorists; Rakhmat Akilov, Mohamed Bouhlel and Salman Abedi. The report further considers what role Melder ́s eight existential dimensions play in violent Islamic radicalization. The analyzis is based on a deductive method where, as said above, the conversion theory, existential dimensions and risk factors are used to answer the research questions. This study analyses and encodes the material by hand with paper and pen, even though the program “OpenCode” is more commonly used in a thesis of this proportion, due to it provided a more flexibility. The conclusion of this study is that Rambo ́s theory can elucidate violent reli- gious Islamic radicalization but as the theory tends to be too broad and vague it should be used in combination with other theories to be able to fully explain the conversion. Other- wise the theory tends to be too broad and vague. Results of analyzing the risk factors and existential dimensions, shows that there are more similarities between the three terrorists than differences and that the existential dimensions do play an important role in the religious radicalization even though this theo- ry also can be to broad and vague because of a tendency by the dimensions to overlap.