Kos’ fertile land attracted settlers from the earliest days. So many people lived here by Mycenaean times that it sent 30 ships to the Trojan War. During the 7th and 6th centuries BC Kos prospered as an ally of the powerful Rhodian cities of Ialysos, Kamiros and Lindos. In 477 BC, after suffering an earthquake and subjugation to the Persians, it joined the Delian League and again flourished.
Hippocrates (460–377 BC), the ancient-Greek physician known as the founder of medicine, was born and lived on the island. After Hippocrates’ death, the Sanctuary of Asclepius and a medical school were built, which perpetuated his teachings and made Kos famous throughout the Greek world.
Ptolemy II of Egypt was born on Kos, thus securing it the protection of Egypt, under which it became a prosperous trading centre. In 130 BC Kos came under Roman domination, and in the 1st century AD it was administered by Rhodes, with which it came to share the same vicissitudes, right up to the tourist deluge of the present day.