The Thracians are undoubtedly connected to the past of Bulgaria. The preserved written information about their culture is often incomplete or subject to interpretation. According to them the appearance of the Thracian ethno-cultural community dates to the middle and late Bronze Age.
During the bigger part of their history the Thracians were separated into different tribes. In the period between centuries V-I BC the famous Thracian Odrysian Kingdom existed. It is probably what has left the Bulgarian archeology the considerable cultural heritage, which includes Sevtopolis, the golden mask of Teres, the bronze head of Sevt III, the golden treasure from Panagyurishte and a range of other precious artefacts. The Thracian culture is defined by the achievements and peculiarities in the field of mythology, architecture, sculpture, wall painting, everyday life and arts. A typical thing are the features of the forming of cities and reinforced palaces (Kabile, Sevtopolis), cult centers with necropolises (Valley of the Thracian Kings, Starosel, Perperek, Tatul and Sborianovo) and monumental tombs with sculptures and painted ornaments (Aleksandrovo, Strelcha, Mezek, Starosel, Shipka, Kazanlak, Sveshtari). The rich findings of precious metals (Vratsa, Rozovets, Duvanli and so on) are of an exquisite design (the Panagyurishte Treasure, the Treasure from Rogozen and so on). The Thracian tradition of tomb building is also connected to the late antique age – the Golden Treasure of Valchitran, which is connected to specific ritual ceremonies of the sun cult. Another thing connected to the sun cult to the priest-kings, symbolizing the Sun, are the rock burial grounds in Eastern Rhodopes and the Thracian megaliths, which are also known in other parts of Bulgaria.
Towards centuries I-II AD the Roman expansion in the Balkans conquered most of the Thracian lands. During century III, however, the Roman Empire falls into a heavy crisis, brought about by inner power struggles. That weakened the military strength of the empire to a degree and the Thracian provinces became an arena for the invading Goths and other barbaric tribes. As a result towards centuries III-V the root Thracian population had already been significantly reduced – part of it had been removed and another part assimilated. The numerous priceless artefacts and objects, which reminded of the achievements of the Thracians and their civilization, however, remained.