History chronicles reveal that after conquering the Rhodopi Mountains in the middle of 14th century, Ivan Alexander of Bulgaria appointed his representative for the region. This is now supported by the evidence found in the ruins of the old castle, which include coins and fragments of expensive porcelain. The Perperikon region is the place where the only golden seal belonging to Ivan Alexander was discovered, now property of an American collector.
According to the head of the expedition Nikolay Ovcharov, this fortress was of utmost importance, because of its highly secure fortification and the immediate proximity to Bulgaria's biggest goldmines.