Greece - Passport & Nationality - Greek Citizenship - Grandparent born in Greece
Greek emigrants and their direct descendants (e.g. children and grandchildren) may apply for Greek citizenship in some circumstances. The key requirement is that a grandparent was born in Greece. The relevant parent(s) or grandparent(s) do not need to still be alive.
Greece is a member of the European Union. As a result, a Greek passport holder can live and work in any of the EU member states (including Ireland).