Europe, until recently, suffered from lower levels of terrorism than most other regions of the world. Prior to 9/11, nationalist groups and left-wing groups accounted for most of the terrorist attacks. With the increase of religious terrorism before and after 9/11, there have been increases in terrorist incidents, especially in 2016 and 2017, by Islamic extremists linked to Islamic State in Iraq and Syria (ISIS). The attacks by Islamic extremists have in turn been associated with increased activity by right-wing extremist groups. This chapter examines the evolution of religiously motivated terrorism in Europe since 9/11 and the related development of right wing extremism and its implications for political order.