According to mythology, Artemis, in order to punish the king of the city of Kalydon of Aetolia, Oeneus, sent a frightful boar to the city. Meleagros, the king's son, killed the boar, but this irreverence cost him his life. His sisters were lamenting his death, and the goddess, taking pity of them, turned them into hens and gave them the name of Meleagrids. She established them on her island, Leros, which had just emerged from the sea, and whose marshland could provide food for them.

The first inhabitants of Leros where Carians, Phoenicians, Lelegians and Eteokritans. Lerians took part in the Trojan War along with Kalymnians. After the Persian Wars, the island joined the Athenian Leaque and after the Peloponnesian War passed into the possession of the Spartans. Very few things are known about the Hellenistic and Roman era. Much later, pirates devastated the island, and since 1455, the Turks kept ravaging it and killing the inhabitants. In 1522, it was captured by the Turks and its inhabitants secured special privileges from the Sultan. In 1648, the island was taken by the Venetian Foscolo Leonardo. Leros played an important part during the Greek War of Independence of 1821. It became part of Greece until 1830 when it was returned to the Turks until 1912 according to the Protocol of London in 1830. Then it was the Italians turn to set foot in the Dodecanese. On 7 March 1948, it was finally united with the rest of the Greek state along with the rest of the Dodecanese islands.