In the years that followed, however, Kalymnos shifted allegiance on several occasions until it ended up to the Spartan camp. Ultimately, it was invaded and occupied by the Persians. In the year 333 B.C. Kalymnos was liberated by Ptolemaeus.
The year 144 B.C. saw the subjugation of the island by the Romans, Kalymnos having had taken sides with the latter in their war against Philip the Fifth. Whereas in the beginning the Romans bequeathed several privileges to Kalymnos, the island later suffered from heavy taxation and looting raids that eventually deprived the place of much of its wealth, reducing its population to misery.
In the Byzantine years, Kalymnos experienced several raids by the pirates that infested the seas of the time, calamities that only came to aggravate the dire circumstances of an island often ravaged by such natural disasters as earthquakes - the worst of which shook Kalymnos in AD 533 strongly enough to change its shape.
During the Dominion of the Francs (AD 1204 -1261) Kalymnos managed to remain under Byzantine rule and its administration exercised from the city of Nikaea, until the year 1306, when it was acquired by the Knights of Saint John, part of the estate of who it continued to be through to 1522. Corsair raids and natural disasters - mostly earthquakes - continued to torment the island all through the time of the Knights.
The Turks also ravaged the island on several occasions until the managed to settle here as masters, which did not prevent the pirates from pursuing their rapacious activities whenever they chose. So critical the problem had become that the inhabitants of the island were allowed to take to the arms to protect themselves. Interestingly, this brought the Kalymnians to a preferred position of readiness when the Greek nation rose to shake the Ottoman rule. Nevertheless, it was only in 1912 that Kalymnos was liberated from the Turkish oppressors.
The place of the Turks was taken by the Italians, until 1948 when, after many adventures, the island became definitively part of the Greek Territory.
Throughout its history, Kalymnos has been closely associated with the world of the sea. It is thus small wonder that the feats and excellence of the Kalymnians at sea and most particularly in the cropping of sea sponges made the reputation of the island, bringing wealth and prosperity.