In
Ancient Greece, a
deme or
demos was a suburb of Athens or a subdivision of
Attica, the region of
Greece surrounding
Athens. Demes as simple subdivisions of land in the countryside seem to have 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 city of Athens itself, where they had not previously existed; in all, at the end of Cleisthenes' reforms, Attica was divided into 139 demes to which one should add Berenikidai, established in 224/223 BC, Apollonieis (201/200 BC) and Antinoeis (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.