Today, the environment seems omnipresent in European policy within and beyond the European Union. The idea of a shared European environment, however, has come a long way and is still being contested. Greening Europe focuses on the many ways people have interacted with nature and made it an issue of European concern. The authors ask how notions of Europe mattered in these activities and they expose the many entanglements of activists across the subcontinent who set out to connect and network, and to exchange knowledge, worldviews, and strategies that exceeded their national horizons. Moving beyond human agency, the handbook also highlights the eminent role nature played in both "greening" Europe and making Europe a shared environment.