Zalmoxis is a deity associated with religious beliefs among the ancient Thracians, who were an Indo-European people inhabiting the region of Thrace in the Balkans during antiquity. The name “Zalmoxis” is of uncertain origin and has been interpreted differently by scholars. Zalmoxis is primarily known from the writings of the Greek historian Herodotus, who traveled through the region and recorded his observations. According to Herodotus, Zalmoxis was a slave of Pythagoras, the Greek philosopher and mathematician, before becoming a divine figure worshipped by the Thracians. Zalmoxis was believed to be immortal and possessed knowledge of the afterlife. The Thracians practiced a form of immortality ritual, where they would send a representative to “visit” Zalmoxis in an underground chamber, conveying messages and offerings to him. This ritual was likely connected to their beliefs in the afterlife and the idea of life beyond death. The worship of Zalmoxis reflects the ancient Thracian’s spiritual beliefs, which were characterized by a mix of indigenous traditions and influences from neighboring cultures. The exact nature of the cult of Zalmoxis remains somewhat enigmatic, as ancient sources provide limited information about the deity and the religious practices associated with him. Nonetheless, Zalmoxis holds a significant place in the religious landscape of ancient Thrace and highlights the diverse and complex belief systems of ancient peoples. The study of Zalmoxis provides insights into the religious syncretism and the intertwining of myth and history in the ancient Balkans.