The political party Prasini Politiki (Greek: Πράσινη Πολιτική, "Green Politics"), the body that lead to the establishment of the party under the name "Oikologoi Prasinoi", was founded in 1996 and already registered as the Greek member of the European Green Party, including other local ecological groups and independent ecologists, like the Ecological Forum (Οικολογικό Φόρουμ) and the Ecological Movement of Thessaloniki.

During 7–8 December 2002, the "Prasini Politiki" council called for a conference that convened in the building of the Athens Lawyer Association, and it decided to establish the Ecologist Greens and elected an 18-member council to coordinate the establishment of a new political entity.

In the coming months, focus groups were created to shape the constitution and the political positions of the body, which were adopted by the first congress of the party in May 2003 at Panteion University.

Alexis Tsipras' called for unity against the Memorandum[2] and the Ecologist Greens decided to support SYRIZA's electoral list for the upcoming legislative election.

[5] The basic principles of the Ecologists Greens (Oikologoi Prasinoi), as determined by their constitution[6] are: sustainability, social justice, nonviolence, direct and participatory democracy, respect for diversity, decentralization and subsidiarity, protect and restore natural ecosystems, the quality of life, personal and social responsibility, equity and anti-austerity.