The town was founded in ancient times. The Greek geographer Pausanias in his book "Messiniaka" reports the original location of Koroni at today's Petalidi, a town a few kilometers north of Koroni. He also reports many temples of Greek gods and a copper statue of Zeus. Because of reorderings, in the centuries that followed the town of Koroni moved to its current location where the ancient town of Asini had once stood. In the 6th and 7th centuries AD, the Byzantines built a fortress there. In 1206, the Venetians occupied it, turning Koroni into an important stage on their sea routes towards the Eastern Mediterranean.
The fortress and town were captured by the Ottoman troops of Sultan Bayezid II in 1500. Apart from a short period under Habsburg Empire rule in the Siege of Coron in 1532-1534, when the fortress was defended by a few noble families as Baffa Trasci, Stratigò and Marchianò, as well as a short return to Venetian rule (1686–1715) after the Morean War, they remained under the control of the Ottoman Empire until becoming part of the modern Greek state in 1828 when it was liberated by the French General Nicolas Joseph Maison
