Empire of Nicaea in the context of "Latin Emperor"

Arbanon (Old Gheg: Arbënia, Old Tosk: Arbëria; Latin: Arbanum) was a medieval principality in present-day Albania, ruled by the native Progoni family, and the first Albanian state to emerge in recorded history. The principality was established in 1190 by the Albanian archon Progon in the region surrounding Kruja, to the east and northeast of Venetian territories. Progon was succeeded by his sons Gjin and then Demetrius, who managed to retain a considerable degree of autonomy from the Byzantine Empire. In 1204, Arbanon attained full, though temporary, political independence, taking advantage of the weakening of Constantinople following its pillage during the Fourth Crusade. However, Arbanon lost its large autonomy c. 1216, when the ruler of Epirus, Michael I Komnenos Doukas, started an invasion northward into Albania and Macedonia, taking Kruja and ending the independence of the principality. From this year, after the death of Demetrius, the last ruler of the Progoni family, Arbanon was successively controlled by the Despotate of Epirus, then by the Bulgarian Empire and, from 1235, by the Empire of Nicaea.

During this period, the area was ruled by the Greco-Albanian lord Gregorios Kamonas, the new spouse of Demetrius' Serbian former wife Komnena Nemanjić, and by Golem (Gulam), a local magnate who had married Kamonas' and Komnena's daughter. Arbanon was eventually annexed in the winter of 1256–57 by the Byzantine statesman George Akropolites. Golem subsequently disappeared from historical records. Akropolites' historical writings are the main primary source for late Arbanon and its history.

The sack of Constantinople occurred in April 1204 and marked the culmination of the Fourth Crusade. Crusaders sacked and destroyed most of Constantinople, the capital of the Byzantine Empire. After the capture of the city, the Latin Empire (known to the Byzantines as the Frankokratia, or the Latin occupation) was established and Baldwin IX of Flanders crowned emperor in Hagia Sophia.

After the city's sacking, most of the Byzantine Empire's territories were divided up among the Crusaders. Byzantine aristocrats also established a number of small independent splinter states—one of them being the Empire of Nicaea, which eventually recaptured Constantinople in 1261 and proclaimed the reinstatement of the Empire. However, the restored Empire never managed to reclaim all its former territory or attain its earlier economic strength, and it gradually succumbed to the rising Ottoman Empire over the following two centuries.

The Despotate of Epirus (Medieval Greek: Δεσποτᾶτον τῆς Ἠπείρου) was one of the Greek rump states of the Byzantine Empire established in the aftermath of the Fourth Crusade in 1204 by a branch of the Angelos dynasty. It claimed to be the legitimate successor of the Byzantine Empire during the subsequent struggle for Constantinople, along with the Empire of Nicaea and the Empire of Trebizond; its rulers briefly proclaiming themselves as Emperors in 1227–1242 (during which it is most often called the Empire of Thessalonica). The term "Despotate of Epirus" is, like "Byzantine Empire" itself, a modern historiographic convention and not a name in use at the time.

The Despotate was centred on the region of Epirus, encompassing also Albania and the western portion of Greek Macedonia and also included Thessaly and western Greece as far south as Nafpaktos. Through a policy of aggressive expansion under Theodore Komnenos Doukas the Despotate of Epirus also briefly came to incorporate central Macedonia, with the establishment of the Empire of Thessalonica in 1224, and Thrace as far east as Didymoteicho and Adrianople, and was on the verge of recapturing Constantinople and restoring the Byzantine Empire before the Battle of Klokotnitsa in 1230 where he was defeated by the Bulgarian Empire. After that, the Epirote state contracted to its core in Epirus and Thessaly, and was forced into vassalage to other regional powers. It nevertheless managed to retain its autonomy until being conquered by the restored Palaiologan Byzantine Empire in ca. 1337. In the 1410s, Carlo I Tocco, Count Palatine of Cephalonia and Zakynthos, managed to reunite the core of the Epirote state, but his successors gradually lost it to the advancing Ottoman Empire, with the last stronghold, Vonitsa, falling to the Ottomans in 1479.

Byzantine Anatolia refers to the peninsula of Anatolia (located in present-day Turkey) during the rule of the Byzantine Empire. Anatolia was of vital importance to the empire following the Muslim invasion of Syria and Egypt during the reign of the Byzantine Emperor Heraclius in the years 634–645 AD. Over the next two hundred and fifty years, the region suffered constant raids by Arab Muslim forces raiding mainly from the cities of Antioch, Tarsus, and Aleppo near the Anatolian borders. However, the Byzantine Empire maintained control over the Anatolian peninsula until the High Middle Ages (years 1080s), when imperial authority in the area began to collapse.

The Byzantine Empire re-established control over parts of Anatolia during the First Crusade, and following the sack of Constantinople during the Fourth Crusade, Anatolia became the heartland of the successor states of the Empire of Nicaea and Empire of Trebizond. Following the retaking of Constantinople in 1261, the region gradually passed out of Byzantine control and into the hands of the Ottoman Turks as the empire gradually crumbled. The last Byzantine fortress of Philadelphia fell in 1399, and the last Byzantine presence in the area at Trapezus ended in 1461 with the fall of Trebizond.

Theodore Komnenos Doukas (Greek: Θεόδωρος Κομνηνὸς Δούκας, Theodōros Komnēnos Doukas; Latinized as Theodore Comnenus Ducas; died c. 1253) or Theodore Angelos Komnenos was the ruler of Epirus and Thessaly from 1215 to 1230 and of Thessalonica and most of Macedonia and western Thrace from 1224 to 1230. He was also the power behind the rule of his sons John and Demetrios over Thessalonica in 1237–1246.

Theodore was the scion of a distinguished Byzantine aristocratic family related to the imperial Komnenos, Doukas, and Angelos dynasties. Nevertheless, nothing is known about Theodore's life before the conquest of Constantinople and dissolution of the Byzantine Empire by the Fourth Crusade in 1204. Following the fall of Constantinople, he served Theodore I Laskaris, founder of the Empire of Nicaea, for a few years before being called to Epirus, where his half-brother Michael I Komnenos Doukas had founded an independent principality. When Michael died in 1215, Theodore sidelined his brother's underage and illegitimate son Michael II and assumed the governance of the Epirote state. Theodore continued his brother's policy of territorial expansion. Allied with Serbia, he expanded into Macedonia, threatening the Latin Kingdom of Thessalonica. The capture of the Latin Emperor Peter II of Courtenay in 1217 opened the way to the gradual envelopment of Thessalonica, culminating in the city's fall in 1224.

The Empire of Thessalonica is a historiographic term used by some modern scholars to refer to the short-lived Byzantine Greek state centred on the city of Thessalonica between 1224 and 1246 (sensu stricto until 1242) and ruled by the Komnenodoukas dynasty of Epirus. At the time of its establishment during the struggle for Constantinople, the Empire of Thessalonica, under the capable Theodore Komnenos Doukas, rivaled the Empire of Nicaea and the Second Bulgarian Empire as the strongest state in the region, and aspired to capturing Constantinople, putting an end to the Latin Empire, and restoring the Byzantine Empire that had been extinguished in 1204.

Thessalonica's ascendancy was brief, ending with the disastrous Battle of Klokotnitsa against Bulgaria in 1230, where Theodore Komnenos Doukas was captured. Reduced to a Bulgarian vassal, Theodore's brother and successor Manuel Komnenos Doukas was unable to prevent the loss of most of his brother's conquests in Macedonia and Thrace, while the original nucleus of the state, Epirus, broke free under Michael II Komnenos Doukas. Theodore recovered Thessalonica in 1237, installing his son John Komnenos Doukas, and after him Demetrios Angelos Doukas, as rulers of the city, while Manuel, with Nicaean support, seized Thessaly. The rulers of Thessalonica bore the imperial title from 1225/7 until 1242, when they were forced to renounce it and recognize the suzerainty of the rival Empire of Nicaea. The Komnenodoukai continued to rule as Despots of Thessalonica for four more years after that, but in 1246 the city was annexed by Nicaea.

Nicaea (also spelled Nicæa or Nicea, /naɪˈsiːə/ ny-SEE-ə; Latin: [niːˈkae̯.a]), also known as Nikaia (Ancient Greek: Νίκαια, Attic: [nǐːkai̯a], Koine: [ˈnikεa]), was an ancient Greek city in the northwestern Anatolian region of Bithynia.

It was the site of the First and Second Councils of Nicaea (the first and seventh Ecumenical councils in the early history of the Christian Church). The Nicene Creed, which was composed at the First Council, takes its name from the city. It was also the capital city of the Empire of Nicaea following the Fourth Crusade in 1204, until the recapture of Constantinople by the Byzantines in 1261. Nicaea was also the capital of the Ottomans from 1331 to 1335.

The Palaiologan army refers to the military forces of the Byzantine Empire under the rule of the Palaiologos dynasty, from the late 13th century to its final collapse in the mid-15th century. The army was a direct continuation of the forces of the Empire of Nicaea, which itself was a fractured component of the formidable Komnenian army of the 12th century. Under the first Palaiologan emperor, Michael VIII, the army's role took an increasingly offensive role whilst the naval forces of the empire, weakened since the days of Andronikos I Komnenos, were boosted to include thousands of skilled sailors and some 80 ships. Due to the lack of land to support the army, the empire required the use of large numbers of mercenaries.

After Andronikos II took to the throne in 1282, the army fell apart and the Byzantines suffered regular defeats at the hands of their eastern opponents, although they would continue to enjoy success against the Latin territories in Greece. By c. 1350 the Empire's inefficient fiscal organization and incompetent central government made raising troops and the supplies to maintain them a near-impossible task, and the Empire came to rely upon troops provided by Serbs, Bulgarians, Venetians, Latins, Genoese and Turks to fight the civil wars that lasted for the greater part of the 14th century, with the latter foe being the most successful in establishing a foothold in Thrace. By the time the civil war had ended, the Turks had cut off Constantinople, the capital of the Byzantine Empire, from the surrounding land and in 1453 the last decisive battle was fought by the Palaiologan army when the capital was stormed and sacked, falling on 29 May.