Siege of Constantinople

The siege of Constantinople in 1260 was the failed attempt by the Nicene Empire, the major remnant of the fractured Byzantine Empire, to retake Constantinople from the Latin Empire and re-establish the City as the political, cultural and spiritual capital of a revived Byzantine Empire. Background Following the Sack of Constantinople by the Fourth Crusade in April 1204, the Byzantine Empire was divided among Latin Crusader states and a few Byzantine Greek remnants, the chief of which were the Despotate of Epirus in western Greece and Albania, and the Nicaean Empire in western and northwestern Asia Minor. Both of the latter claimed to represent the legitimate Empire, and in view of the weakness of the Latin Empire, vied for the recovery of Constantinople. At first it seemed as if the city would fall to Epirus, whose ruler Theodore Komnenos Doukas crowned himself emperor at Thessalonica in 1225/1227. Epirote power however was broken at the Battle of Klokotnitsa in 1230 against Bulgaria. Thus the path opened up for Nicaea, under John III Doukas Vatatzes (r. 1221–1254), to intervene in Europe. Allied with the Bulgarians, Vatatzes established a first foothold in Thrace in 1234. Together with the Bulgarians, he then undertook an unsuccessful siege of the city in 1235–6. Thereafter, the Nicaean ruler switched his aim to increasing his territory in Europe. Under Vatatzes, the Nicaeans seized most of Thrace and Macedonia from Epirus and Bulgaria, becoming the strongest state of the region. Reduced to Constantinople and the territory immediately surrounding it, surrounded on east and west by Nicaea and without sufficient funds to attract any armed support, the Latin Empire seemed ripe for the taking by the time of Vatatzes' death. Even the papacy seemed willing to accept the inevitable in exchange for concessions in theological matters and the question of papal primacy. The Latin Empire gained a short reprieve with Vatatzes' death, as his son and successor Theodore II Laskaris (r. 1254–1258) was forced to confront numerous attacks on his territories in the Balkans. Soon after Theodore II's death, the ambitious Michael VIII Palaiologos (r. 1259–1282) ascended the throne, at first ostensibly as guardian of the infant John IV Laskaris (r. 1259–1261). At this juncture, a coalition of Nicaea's enemies was formed, comprising Epirus, the Principality of Achaea, and the Kingdom of Sicily.