European integration is the process of industrial, economic, political, legal, social, and cultural integration of states wholly or partially in Europe, or nearby. European integration has primarily but not exclusively come about through the European Union and its policies.

Altiero Spinelli was an Italian communist politician, political theorist and European federalist, referred to as one of the founding fathers of the European Union. A communist and militant anti-fascist in his youth, Spinelli spent 10 years imprisoned by the Italian fascist regime. Having grown disillusioned with Stalinism, he broke with the Communist Party of Italy in 1937. Interned in Ventotene during World War II, he, along with fellow democratic socialists, drafted the manifesto For a Free and United Europe in 1941, considered a precursor of the European integration process.