Archon (meaning, simply, "the ruling one") was the title given to public officials in several Greek states. Archons are attested in Arcadia, Athens, Boiotia, Delos, Delphi, Thessaly (where four "tetrarchs" each ruled a "tetrad" or "fourth" of Thessaly), and elsewhere.
In Athens, in the Classical period, there were three annually selected archons, the archon basileus (or "king" archon), the polemarch (or "war" archon), and the undifferentiated "archon" who gave his name to the year in public documents and is often called the "eponymous archon." The functions of the archons represent the powers of a king divided up amongst three men, with the archon basileus having mostly religious duties, the polemarch having, at least originally, the role of war leader, and the archon holding administrative power. The Athenians believed that this system developed out of the early monarchy in stages, with archons serving first for life, then for ten-year terms ([Arist.] Ath. Pol. 3.1–2). The tradition put the first annual archons in 683/2 bce (see Kreon, Athenian Archon). At some time, possibly in the mid to late seventh century (Rhodes 1993: 102), six annually appointed thesmothetai were added to the college of archons. After their year of service, archons became life members of the council of the Areopagos.
Originally the archonship was open only to the nobility and archons were chosen by election or were appointed by the council of the Areopagos ([Arist.] Ath. Pol. 8.2). According to the Athenaion Politeia, Solon in 594/3 instituted a change whereby archons were appointed by lot from a shortlist of candidates elected by the tribes, but this is controversial ([Arist.] Ath. Pol. 8.1; Hansen 1991: 49–52; Rhodes 1993: 146–8). Solon also changed the qualification for office from birth to wealth. It is not clear if he opened the archonship only to his top census class, the Pentakosiomedimnoi or "five-hundred-bushel men," or to the Hippeis or "knights" as well ([Arist.] Ath. Pol. 7.3). The third class of Zeugitai or "yoke-men" became eligible for the archonship in 457/6 ([Arist.] Ath. Pol. 26.2) so the hippeis must have gained eligibility for the archonship before that date and probably by 487/6. In that year, after the tyranny of the Peisistratids and its aftermath, during which archons were elected, men were appointed by lot to the archonship from a shortlist of (probably one hundred) men elected by the ten Kleisthenic tribes. At some later point, appointment by lot replaced election even for the shortlist of candidates chosen by the tribes ([Arist.] Ath. Pol. 8.1; 55.1). That archons were chosen by lot and served for only one year is probably the reason for the diminution of the importance of the office in the fifth and fourth centuries. Politically ambitious men turned to the office of strategos or general, and it is this office that, for example, Perikles held repeatedly, not the archonship.
There were also other lesser archons in Athens. Each Kleisthenic deme had an archon (the "demarch") who convened the deme assembly and executed its decisions. The non-deme community resident on the island of Salamis had an archon who probably served a function much like a demarch for an official deme. Even private ethnic and religious organizations like the genos of the Salaminioi might organize themselves under an archon. An archon might also be a military official. The phylarch commanded the troops from a tribe (or phyle), a taxiarch, a given corps (or taxis).
In the fifth century, Athens also sent archons abroad to help administer the empire. The Athenaion Politeia gives their number as 700, but this figure is controversial (Arist. [Ath. Pol.] 24.3). These archons included men called more specifically "overseers" and "garrison commanders" as well as officials called simply "archons." Inscriptions indicate that these resident officials helped establish new governments in cities that had revolted, worked to ensure that Athenian decrees were followed, and oversaw the collection of Tribute (cf. Meiggs and Lewis 1969: nos. 45 and 46).
Demes, Attic; Genos, Gene; Kleisthenes of Athens; Strategoi.