Whether choice of law in international contracts includes not only the law of a state but so-called non-state law is a question that has not only engaged legal scholars but also the European legislator. This study retraces the influence of EU law on international private law and non-state law making. The author examines works of European contract law such as DCFR and CESL and differentiates them from superordinate concepts such as lex mercatoria and soft law. She discusses the concept of party autonomy in European international private law and comes to the conclusion that the choice of works of European contract law is covered by fundamental European rights. De lege ferenda the author proposes to extend the choice of law to non-state law.