The term "Eurypontid" refers to one of the two royal families of ancient Sparta, a prominent city-state in Greece. This dynasty was known for producing several kings who played significant roles in Spartan history, particularly during the classical period. The Eurypontids were often in competition with the other royal family, the Agids, which influenced the political landscape of Sparta. Eurypontid kings were typically involved in military campaigns and governance, contributing to Sparta's reputation as a powerful military state. Notable kings from this lineage include Leonidas I, famous for his leadership at the Battle of Thermopylae. The Eurypontids, alongside the Agids, helped shape the unique dual monarchy system that characterized Spartan rule.