Kos was inhabited from the very early Bronze Age (2900-2100 BC) as the prehistoric tombs and the findings in Asklupi and in the White Stone cave prove. Pelasgi, Kares and Leleges were the first inhabitants. Phoenicians and Achaeans passed through Kos as well.

We can also find relics of the Mycenaean Era or the later Bronze Age (1600-1150 BC). "Karis" and "Meropis" are the ancient names of Kos. Plinios also called it "Nimphea". In the second rhapsody of Iliad, Homer tells us that Kos along with the islands of Nysiros, Kalymnos, Karpathos and Kassos took part in the Trojan War with thirty ships. This was followed by the Dorianization of the island, when, during the 7th and 6th century BC, Kos took part in the Federal Alliance of "Dorian Hexapolis". There is a huge number and variety of ceramics of the Geometric Era, which was brought to light by archeological diggings. The "municipalities", seven in total along with the one of Kos, were formed through the years and the citizens began to prosper. The sailors and merchants that traveled in the Aegean sea, ranked Kos in the same wealth category with the other islands of Asia Minor's coast (Lesbos, Chios, Samos, Rhodes) giving them the name "Makaron Islands".