In Ancient Greece, a deme or demos (Ancient Greek: δῆμος, plural: demoi, δῆμοι) was a suburb or a subdivision of Athens and other city-states. Demes as simple subdivisions of land in the countryside existed in the 6th century BC and earlier, but did not acquire particular significance until the reforms of Cleisthenes in 508 BC. In those reforms, enrollment in the citizen-lists of a deme became the requirement for citizenship; prior to that time, citizenship had been based on membership in a phratry, or family group. At this same time, demes were established in the main city of Athens itself, where they had not previously existed; in all, at the end of Cleisthenes' reforms, Athens was divided into 139 demes. Three other demes were created subsequently: Berenikidai (224/223 BC), Apollonieis (201/200 BC), and Antinoeis (AD 126/127). The establishment of demes as the fundamental units of the state weakened the gene, or aristocratic family groups, that had dominated the phratries.
A deme functioned to some degree as a polis in miniature, and indeed some demes, such as Eleusis and Acharnae, were in fact significant towns. Each deme had a demarchos who supervised its affairs; various other civil, religious, and military functionaries existed in various demes. Demes held their own religious festivals and collected and spent revenue.
