The Battle of Pelagonia took place in September of 1259, between the Empire of Nicaea and the Principality of Achaea. It was a decisive event in the Near East history, ensuring the Byzantine reconquest of Constantinople and the end of the Latin Empire in 1261, and marks the beginning of the Byzantine recovery of Greece. For broader historical context, see 1250s and 13th century. ... Pelagonia was an ancient region of Europe later incorporated into Macedon. ... The Empire of Nicaea was the largest of the states founded by refugees from the Byzantine Empire after Constantinople was conquered during the Fourth Crusade. ... The Principality of Achaea was one of the three vassal states of the Latin Empire which replaced the Byzantine Empire after the capture of Constantinople during the Fourth Crusade. ... The Empire of Nicaea was the largest of the states founded by refugees from the Byzantine Empire after Constantinople was conquered during the Fourth Crusade. ... William II Villehardouin (died May 1, 1278) was the last Villehardouin prince of Achaea (=Morea) and ruled the principality at the height of its power and influence. ... For broader historical context, see 1250s and 13th century. ... The Empire of Nicaea was the largest of the states founded by refugees from the Byzantine Empire after Constantinople was conquered during the Fourth Crusade. ... The Principality of Achaea was one of the three vassal states of the Latin Empire which replaced the Byzantine Empire after the capture of Constantinople during the Fourth Crusade. ... Map of Constantinople. ... The Latin Empire, Empire of Nicaea, Empire of Trebizond and the Despotate of Epirus. ...

Nicaean emperor Theodore II Laskaris died in 1258 and was succeeded by the young John IV Laskaris, under the regency of Michael VIII Palaiologos, who was determined to restore the Byzantine Empire and recapture all of the territory it held before the Fourth Crusade. In 1259 William II Villehardouin married Anna Komnena Dukaina (also known as Agnes), daughter of Michael II of Epirus, cementing an alliance between the Despotate of Epirus and Achaea against Nicaea. They also allied with Manfred of Sicily who sent them 400 knights. Theodore II Doukas Laskaris or Ducas Lascaris (Greek: Θεόδωρος Β΄ Δούκας Λάσκαρις, Theodōros II Doukas Laskaris) (1221/1222–August 18, 1258) was emperor of Nicaea, 1254–1258. ... For broader historical context, see 1250s and 13th century. ... John IV Doukas Laskaris or Ducas Lascaris (Greek: Ιωάννης Δ΄ Δούκας Λάσκαρις, Iōannēs IV Doukas Laskaris), December 25, 1250 - c. ... The Byzantine Empire in 1265 (William R. Shepherd, Historical Atlas, 1911) Michael VIII Palaiologos or Palaeologus (Greek: Μιχαήλ Η΄ Παλαιολόγος, Mikhaēl VIII Palaiologos) (1224/1225 – December 11, 1282) reigned as Byzantine emperor 1259–1282. ... Byzantine Empire at its greatest extent c. ... The Entry of the Crusaders into Constantinople (Eugène Delacroix, 1840). ... William II Villehardouin (died May 1, 1278) was the last Villehardouin prince of Achaea (=Morea) and ruled the principality at the height of its power and influence. ... The Despotate of Epirus was one of the medieval Greek successor states of the Byzantine Empire, founded in the aftermath of the Fourth Crusade in 1204. ... Manfred (c. ...

In 1259 the Nicaeans invaded Thessaly and in September the Achaean and Epirote army marched north to meet them. The Nicaeans were led by the sebastocrator Theodore Ducas, the brother of Michael II of Epirus. According to the French Chronicle of Morea, The Nicaean force consisted of the main Byzantine army, with Turkish mercenaries, 2000 Cumans, 300 Germans, 13 000 Hungarians, 4000 Serbs and Bulgarians, and some Vlachs. There were suppposedly 27 cavalry divisions, although all of these numbers are probably exaggerated. Theodore also gathered all the local peasants and their flocks and placed them on the hilltops, so that from far away they might appear to be part of the army. Map showing Thessaly periphery in Greece Thessaly (Θεσσαλια; modern Greek Thessalía; see also List of traditional Greek place names) is one of the 13 peripheries of Greece, and is further sub-divided into 4 prefectures. ... Painting of Emperor Basil II, exemplifying the Imperial Crown handed down by Angels. ... The name Morea (Greek: Μωρέας or Μωριάς) was used to refer to the Peloponnese peninsula in southern Greece during the Middle Ages and the early modern period. ... A mercenary is a person who takes part in an armed conflict who is not a national of a Party to the conflict and is motivated to take part in the hostilities essentially by the desire for private gain and, in fact, is promised, by or on behalf of a... Cuman, also called Polovtsy, Polovtsian, or the Anglicized Polovzian (Russian: , Ukrainian: , Bulgarian: , Romanian: , Hungarian: ), is a Western European exonym for the western Kipchaks. ... Anthem Serbia() on the European continent() Capital (and largest city) Belgrade Official languages Serbian 1 Recognised regional languages Hungarian, Croatian, Slovak, Romanian, Rusyn 2 Albanian 3 Government Semi-presidential republic  -  President Boris Tadić  -  Prime Minister Vojislav KoÅ¡tunica Establishment  -  Formation 9th century   -  First unified state c. ... Map of Romania with Wallachia in yellow. ...

Theodore then sent a false deserter to Michael II and William, exaggerating the number of Nicaean troops and chastizing Michael for attempting to attack a family member. The duke of Carinthia, who also had 300 Germans with him, did not believe the deserter, and convinced the Achaeans to stay when they decided to flee. Still, Michael and his troops deserted during the night and fled to the Nicaean side; according to George Pachymeres this is because Michael's illegitimate son John quarrelled with William. Coat of arms of the Dukes of Carinthia, today state coat The Duchy of Carinthia (German language: Kärnten, Slovenian: Koroška) was a duchy of the Holy Roman Empire until its dissolution in 1806, and a crownland of Austria-Hungary until it dissolved in 1918. ... Georgius Pachymeres (1242-c. ...

On the next day, the Germans under the duke of Carinthia attacked their fellow German mercenaries on the Nicaean side. The duke was killed in the fight. The Hungarian archers then killed all the Achaean horses, leaving the knights effectively defenceless. The Achaean foot soldiers fled and the knights surrendered; prince William fled as well and hid under a nearby haystack where he was soon captured. Theodore brought him to John Palaiologos, brother of Michael VIII, who was in command of the expedition, and William was forced to give up strategic fortresses in Achaea (including Mystras) before he was set free. For a village in the prefecture of Ioannina, see Mystras (Ioannina), Greece The Vale of Laconia seen from the battlements of Mystras Mystras (also Mistra, Mystra and Mistras Greek: Μύστρας , Μυζηθράς Mizithras or Myzithras in the chronicle of Morea ) was a fortified town in Morea (the Peloponnesus), on Mt. ...

John Palaeologus went on to capture Thebes. The Principality of Achaea, which had become the strongest French state in Greece in the aftermath of the Fourth Crusade, was now reduced to Nicaean vassalage; the Duchy of Athens soon became the dominant French state. Michael VIII took advantage of the defeat to recapture Constantinople in 1261. Thebes (Demotic Greek: Θήβα — Thíva; Katharevousa: — Thêbai or Thívai) is a city in Greece, situated to the north of the Cithaeron range, which divides Boeotia from Attica, and on the southern edge of the Boeotian plain. ... // Duchy of Athens A small crusader state which was established after the Sack of Constantinople (1204) by the Crusaders. ... Map of Constantinople. ... Events July 25 - Constantinople re-captured by Nicaean forces under the command of Michael VIII Palaeologus, Byzantine Empire re-formed August 29 - Urban IV becomes Pope, the last man to do so without being a Cardinal first Bela IV of Hungary repels Tatar invasion Charles of Anjou given rule of...

There is a problem with the Chronicle of Morea's claim that the "duke of Carinthia" was present at the battle. The duke at the time was Ulrich III, but he ruled for many years after 1259, and was probably not at the battle; the writer of the Chronicle may have invented a fictitious duke as a counterbalance to William. Greek sources, aside from George Pachymeres, include George Acropolites, Nicephorus Gregoras, and George Sphranztes. George Acropolites (Greek: , Georgios Akropolitês) (1217–1282), Byzantine Greek historian and statesman, was born at Constantinople. ... Nicephorus Gregoras (c. ...