→Estrangement and Schism: 1260;1269;
*1259 Byzantines defeat Latin [[w:Principality of Achaea|Principality of Achaea]] at the [[w:Battle of Pelagonia|Battle of Pelagonia]], marking the beginning of the Byzantine recovery of Greece.
*ca. 1259-80 Martyrdom by Latins of monks of [[Iviron Monastery (Athos)|Iveron Monastery]].
*1261 End of Latin occupation of Constantinople and restoration of Orthodox patriarchs; Emperor Michael VIII Palaiologos makes [[Mystras]] seat of the new [[w:Despotate of Morea|Despotate of Morea]], where a Byzantine renaissance occurred; Pope Urban IV endeavoured without success to stir up a crusade to restore the Latin Empire of Constantinople.
*1263 Roman Catholic theologian Thomas Aquinas writes ''[[w:Contra Errores Graecorum|Contra Errores Graecorum]]'' (''Against the Errors of the Greeks'').
*1264 The festival of [[w:Corpus Christi (feast)|Corpus Christi]] ("the Body of Christ") is instituted by Pope Urban IV.
*1274 [[Council of Lyons]] fails to force Orthodox capitulation to papacy.
*1281 [[w:Pope Martin IV|Pope Martin IV]] authorizes a Crusade against the newly re-established [[Byzantine Empire]] in Constantinople, excommunicating Emperor Michael VIII Palaiologos and the Greeks and renouncing the union of 1274; French and Venetian expeditions set out toward Constantinople but are forced to turn back in the following year due to the [[w:Sicilian Vespers|Sicilian Vespers]].