 Demetrius was the third and last lord of the Progon family, ruling between 1208 (or 1207) and 1216 (or 1215).He succeeded his brother Gjin and brought the principality to its climax.Demetrius styled himself 'panhypersebastos' and 'megas archon' ("Dei gratia panhypersevastos et magnus archon"), and he maintained international relations with the Republic of Ragusa, the Republic of Venice, and Serbia.