The Odrysian Kingdom (; Ancient Greek: ) was a Thracian kingdom that existed from the early 5th century BC at least until the mid-3rd century BC. It consisted mainly of present-day Bulgaria and parts of Southeastern Romania (Northern Dobruja), Northern Greece and European Turkey. Dominated by the eponymous Odrysian people, it was the largest and most powerful Thracian realm and the first larger political entity of the eastern Balkans. Before the foundation of Seuthopolis in the late 4th century it had no fixed capital.