Medon
A herald in the house of Odysseus. (Odyssey of Homer)
2. A son of Oileus and Rhene, and a brother of the lesser Ajax. Having slain Eriopis, one of his mother's kinsmen, he left his father's house, and fled to Phylace. He commanded the Pythians in the war against Troy, and when Philoctetes was wounded, Medon commanded the Methonians in his place. He was slain by Aeneas. (Iliad of Homer)
Two other mythical personages of this name occur in Ovid (Metamorphoses), and Hyginus (Fab. 134).
From Smith's Dictionary of Greek and Roman Biography and MythologyFrom A Smaller History of Greece
A few generations after Theseus, the Dorians are said to have invaded Attica. An oracle declared that they would be victorious if they spared the life of the Athenian King; whereupon Codrus, who then reigned at Athens, resolved to sacrifice himself for the welfare of his country. Accordingly he went into the invaders' camp in disguise, provoked a quarrel with one of the Dorian soldiers and was killed by the latter. Upon learning the death of the Athenian king, the Dorians retired from Attica without striking a blow: and the Athenians, from respect to the memory of Codrus, abolished the title of king, and substituted for it that of Archon or Ruler. The office, however, was held for life, and was confined to the family of Codrus. His son Medon was the first archon, and he was followed in the dignity by eleven members of the family in succession. But soon after the accession Alcmaeon, the thirteenth in descent from Medon, another change was introduced, and the duration of the archonship was limited to ten years (B.C. 752). The dignity was still confined to the descendants of Medon; but in the time of Hippomenes (B.C. 714) this restriction was removed, and the office was thrown open to all the nobles in the state. In B.C. 683 a still more important change took place. The archonship was now made annual, and its duties were distributed among nine persons, all of whom bore the title. The last of the decennial archons was Eryxias, the first of the nine annual archons Creon.
From Description of Greece by Pausanias Book 2
[2.19.2] But from the earliest times the Argives have loved freedom and self-government, and they limited to the utmost the authority of their kings, so that to Medon, the son of Ceisus, and to his descendants was left a kingdom that was such only in name. Meltas, the son of Lacedas, the tenth descendant of Medon, was condemned by the people and deposed altogether from the kingship.