Glarentza (Greek: Γλαρέντζα) is a medieval city located next to the location of today's Kyllini in the Ilia prefecture, Greece.
Glarentza, a corruption of Clarentia or Clarence, was an important city, mint and port during Frankish rule in the Peloponnese. It was built by the Villehardouins of the Principality of Achaea in the location of ancient Cyllene, in Elis during the 13th century.
The importance of the city is shown by the fact that the tornesel, the currency used of the principality of Achaea, bore the legend DE CLARENTIA and later DE CLARENCIA. The Tornesel was introduced into the Principality of Achaea by Robert of Courtenay and Geoffrey II of Villehardouin.
Glarentza's port and its castle were strengthened by the Chlemoutsi fortress in the same area. Glarentza was located 5 to 6 km from Chlemoutsi and 12 to 13 km from Andravida.
The city is mentioned in sources of that period with different names as Grarentza (Γραρέντζα), Klarenza (Κλαρένζα), Klarentsa (Κλαρέντσα), Klorenstia (Κλορένστια) and Kiofentsa (Κιοφέντσα).[1]
Several sources of information on Glarentza are to be found in the Chronicle of Morea, which mentions Klarentza (Κλαρέντζα) (the most closest restitution in Greek of CLARENTIA), around 20 times[2]
In the beginning of the 15th century the whole principality declined in wealth, and Glarentza passed into the possession of the Tocco family. It subsequently changed hands several times, passing between the princes of Achaea, Catalans and once again the Byzantines.
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In 1430, Constantine Palaeologus tore down the wall to make the fortress untenable.
After the establishment of Ottoman rule in Morea and almost the rest of Greece, Glarentza lost its main asset and the location of the most important port. The economic focus of the region was shifted to Patras and Katakolo.
Some believe that Glarentza gave its name to the royal English title the Duke of Clarence; although an Englishman would tell you that it is more likely that the Dukedom of Clarence gets its name from the town of Clare, Suffolk. Glarentza is also mentioned in Zitiano by Andreas Karkavitsas.