The name Damghan comes from "Deh" and "Moghan". "Deh" means village and "Moghan" means Magi. This name was given by Zoroastrians who included such people as King Cyrus and Darius of ancient Persia. Historiographers ascribe the construction of Damghan to Hooshang, Keyumars' great grandson and the founder of the legendary Pishdadi dynasty. The historical town has inherited various names such as Qoomes. Qoomes or Qumis was a province stretching from Sabzevar to Garmsar, from north up to Alborz Mountain Range and to the Lut Desert in the south. Up to the 1st century AD, Damghan was the capital of that great province.
During Alexander of Macedon's invasion into Iran, the Greeks called it Hecatompylos ("hundred gates"). The Greeks called every big and important city Hecatompylos and they have recorded a similar big and bustling Egyptian city with that appellation.
Of historical treasures in Damghan one must refer to the valuable Tappeh Hessar, which was constructed before the birth of Christ. Professor Hertzfeld (1931-1933) and Dr. Schmidt (1933–1938) were the first archaeologists who explored the Tappeh.
Tappeh Hessar, with several layers of civilizations, is hiding a long history in its bosom. Part of the layers in the Tappeh belong to the Mades dynasty, which shared its civilization with Mesopotamia. Another layer covers the Achamenid, Parthian and Seleucid periods. Tappeh Hessar achieved its peak of glory during the Seleucid and Parthian periods. During the reign of Arsaces II, Damghan was the capital of the Parthian Empire in Iran. With the discovery of relics from that period, one comes across another layer, which is ascribed to the Sassanians. Historical excavations has shown that the history of Damghan starts 4–5 thousand years BCE. For example, Carbon 16 isotope inspections in Tappeh Hessar have revealed items belonging to 7,000 years ago. Recently expansion of Tehran–Mashhad railway into double lanes the body of a woman along with her fetus was discovered with over 7,000 years age.
Scientists have discovered metal in her teeth, which leads us to believe that she was the goddess Tootam. Tootam worship was a religion which prevailed among the Iranians, Egyptians and Indians many thousand years ago.
Damghan was half destroyed in the 856 Damghan earthquake.