Leukas (Santa Mavra) did not keep pace with the history of the other islands of the Ionian Sea at all periods. In the 13th century it belonged to the despotate of Epirus.
Most probably the island had been ceded to Giovanni Orsini, the son of the count palatine of Cephalonia and Zakynthos, on the occasion of his marriage to the daughter of the despot of Epirus Nikephoros II, who appears to be Epirus’ seigneur in 1300. According to accounts, during the first years of the Frankish occupation, the population sought refuge in the opposite continental coast. As the dominion of the Orsini family spread over Epirus, Leukas was united with it politically, a unity which was maintained until 1331, when the deposed duke of Athens Gautier de Brienne captured the island as part of a campaign aiming to recapture his acquisitions. His administrative duties were assigned to French deputies. The Orthodox bishopric was abolished and the pope replaced the Orthodox bishop with a Latin one. Only four years later, the Latin bishop mentioned that Catholic priests (canonici) had embraced the Orthodox dogma.
The island followed the luck of Vonitsa, when in 1355 the deposed duke of Athens Gautier de Brienne ceded them both as fiefs to Gratianos Zorzi, his trustee of Venetian origin, who had managed his acquisitions in the past. At the same time, however, the claimants to Epirus grew in number. Among them the most powerful were the Albanian Charles Thopia and Nikephoros, son of the count palatine of Cephalonia and Zakynthos, who both saw the island of Leukas as an extension of the continental coast. Zorzi (or Giorgi) turned for help to Venice in 1357, which responded willingly. But when the Venetian fleet reached the island, its inhabitants - who had been incited by Nikephoros and the new count of Cephalonia and Zakynthos, Leonardo I Tocco - had already risen in rebellion and had arrested Zorzi. Still, the victory of Charles Thopia and the death of Nikephoros gave Zorzi the opportunity to rally his forces, suppress the resistance of the inhabitants and remove the Venetian element from the island. This incident of the inhabitants’ rising against the "authority" inspired, in later years, Aristotle Valaoritis to write Fotinos.
Zorzi continued to be the ruler of Leukas until his death in 1362. Then the inhabitants invited Leonardo I Tocco, the count of Cephalonia and Zakynthos, in order to grant him the governing of the island. In this way, Leukas was incorporated in the same political unit as the other Ionian islands. Naturally, Venice, which aimed at spreading its influence in the Ionian Sea, had reacted to this situation. In 1390, it invoked former privileges of the Venetian family of the Zorzi and protested about the tolls imposed to the Venetian ships that passed from the straight of Saint Mavra. The duchy of the Tocchi in the Ionian islands was abolished by the Turks in 1479 and Leukas remained under the Ottoman rule until 1699.