Definition: The Arimaspians were a group of people who lived in the region around Achaemenian civilization during the 4th century BCE. They are known for their role in building the first Greek city-state, Achaemenid Pella, near modern-day Iran. The term "Arimaspians" is derived from a specific name given to them and is considered to be a reference to their use of Arimaspi (a type of clay) as the building material. They are believed to have been skilled artisans who specialized in creating stone wall structures.