Abstract: Antisemitism was on the rise after 9/11, yet, until 2015, there was weak policy to address it at the national and EU levels. The following examines why and how antisemitism policy emerged on the EU agenda culminating in the creation of the 2021 comprehensive strategy to combat antisemitism. Utilizing punctuated equilibrium theory, crisification literature and literature on Commission entrepreneurship, the article explores why, although other violent attacks had occurred against Jews, it would take the double attacks in 2015 to bring attention to antisemitism within the Commission. Leadership at the EU level, NGOs working with EU institutions, a working definition of antisemitism, along with pre-existent EU legal bases in antidiscrimination law, would help promote antisemitism policy to the EU level. The EU's adoption of antisemitism policy demonstrates both Commission agenda setting and prioritizing antisemitism due to its threat to EU fundamental ideals, thus promoting a ‘European polity’ based on values.