The Battle of Megara occurred in 1359 between an alliance of the Christian states of southern Greece (the Despotate of the Morea, the Principality of Achaea, the Knights Hospitaller and the Republic of Venice), and of a Turkish raiding fleet.

Against the growing menace of Turkish raids in the Aegean Sea, a league was formed, probably at the initiative of Manuel Kantakouzenos, the Despot of the Morea.

It comprised the Byzantines of the Morea, the bailli of the Principality of Achaea, Walter of Lor, the Signoria of the Republic of Venice, and the Knights Hospitaller of Rhodes.

[1] According to the Aragonese version of the Chronicle of the Morea, the allies campaigned in the Megarid, where their navy, composed of Venetian and Hospitaller ships (the latter under the preceptor of Kos, Raymond Berenguer), attacked a Turkish corsair fleet.

[1][2] The Chronicle of the Morea asserts that after the battle, the land contingents of the participants returned home, but according to the history of John VI Kantakouzenos, Manuel's father, the allies launched an invasion of Llúria's Boeotian possessions.