It is possible that had a vote by one of the largest Member States of the European Union on the very membership upon which Citizenship is predicated not taken place in June 2016 during an era of Pan-European populism, a critical deconstructivist approach to the evolution of free movement of persons law might have had purely academic relevance. Whilst European Union Citizenship was ‘born’ in 1992 after the original Treaty of Rome was amended to include Articles 17 and 18, its roots can be excavated to a much earlier period and this book, in a sense, seeks to replicate the Greek Temple façade envisioned by the Maastricht Treaty and examine the structure from its foundations upwards. As early as 1976, Plender famously stated that European Citizenship was ‘incipient’.