Most modern historians believe that the Odrysian kingdom continued to exist throughout the Hellenistic and the early Imperial period, when it became a Roman vassal state. However, the evidence for this assumption is in fact very slim. Throughout the remainder of the 3rd century, Thrace remained fragmented into various political entities. In the interior ruled various badly known Thracian dynasts. In the east was the kingdom of Tylis, a Celtic-dominated predator state which existence was based on blackmailing tribute and that was eventually destroyed by a Thracian revolt or attack soon after 220. In the southeast and based at the town of Lysimachia, the Seleucids established themselves under Antiochus II (r. 261–246), who relied on allied Thracian dynasts to exapand his influence deep into the interior. After his death in 246 the Seleucid presence was replaced by that of the Ptolemies, who established a satrapy in coastal Thrace. An Odrysian kingdom, however, is not described in the sources.