This paper is a historically informed comparative study of militarization and deportation efforts along the Western (Spain–Morocco) and Eastern (Greece–Turkey) Mediterranean migratory routes from 2005 to 2017. Based on extensive fieldwork on both sites, we argue that these two policy instruments go hand-in-hand in the construction of the European Union’s anti-immigration border and examine the continuities in their implementation along the two extremes of the Mediterranean basin. Our findings indicate that the origins of current militarization and deportation efforts in the Eastern Mediterranean (such as the EUROSUR system and the ‘Hot Spots’ approach) can be traced back to the Western Mediterranean and that they have been gradually expanded eastwards. Finally, the paper also demonstrates how militarization and deportation initiatives were implemented jointly by sovereign entities (the EU and member states), and by doing so it addresses the recent debates on the status of sovereignty. We provide evidence to support the argument that, rather than disappearing, sovereignty is re-articulated through cooperation among sovereign entities, despite occasional disagreements among them.