Kingdom of Thessalonica in the context of "Theodore Komnenos Doukas"

Boril (Bulgarian: Борил) was the emperor (tsar) of Bulgaria from 1207 to 1218. He was the son of an unnamed sister of his predecessor, Kaloyan and Kaloyan's brothers, Peter II and Ivan Asen I, who had restored the independent Bulgarian state. After Kaloyan died unexpectedly in October 1207, Boril married his widow, a Cuman princess and seized the throne. His cousin, Ivan Asen, fled from Bulgaria, enabling Boril to strengthen his position. His other kinsmen, Strez and Alexius Slav, refused to acknowledge him as the lawful monarch. Strez took possession of the land between the Struma and Vardar rivers with the support of Stefan Nemanjić of Serbia. Alexius Slav secured his rule in the Rhodope Mountains with the assistance of Henry, the Latin Emperor of Constantinople.

Boril launched unsuccessful military campaigns against the Latin Empire and the Kingdom of Thessalonica during the first years of his reign. He convoked the synod of the Bulgarian Church in early 1211. At the assembly, the bishops condemned the Bogomils for heresy. After an uprising broke out against him in Vidin between 1211 and 1214, he sought the assistance of Andrew II of Hungary, who sent reinforcements to suppress the rebellion. He made peace with the Latin Empire in late 1213 or early 1214. After Henry died in 1216 and Andrew II left Hungary for a crusade, Ivan Asen returned to Bulgaria. He captured and blinded Boril in Tarnovo in 1218.

The Principality of Achaea (/əˈkiːə/) or Principality of Morea was one of the vassal states of the Latin Empire, which replaced the Byzantine Empire after the capture of Constantinople during the Fourth Crusade. It became a vassal of the Kingdom of Thessalonica, along with the Duchy of Athens, until Thessalonica was captured by Epirus in 1224. After this, Achaea became the dominant power in Greece, lasting continuously for 227 years and cumulatively for 229.

The prince of Achaea was the ruler of the Principality of Achaea, one of the crusader states founded in Greece in the aftermath of the Fourth Crusade (1202–1204). The principality witnessed various overlords during its more than two centuries of existence, initially, Achaea was a vassal state of the Kingdom of Thessalonica under Boniface I of house Montferrat, then of the Latin Empire of Constantinople under the houses of Flanders-Courtenay, which had supplanted the Byzantine Empire, and later of the Angevin Kingdom of Naples. During the Angevin period, the princes were often absent, represented in the Principality by their baillis, who governed in their name. After 1404 the principality became sovereign as the Genoese Centurione II Zaccaria bought from the Neapolitan crown the princely rights.

The principality was one of the longest-lasting of the Latin states in Greece, outliving the Latin Empire itself by 171 years. It did not come to an end until 1432, when the Byzantine prince Thomas Palaiologos inherited the last remnants of the Principality through marriage to the daughter of the last prince, Centurione Zaccaria. With the Principality gone, the title of Prince of Achaea became vacant. However, in 1453 during the great Morean revolt of 1453-1454, John Asen Zaccaria, son of Centurione revived the Principality. He was confirmed as Prince by the Kingdom of Naples, the historical overlords of the Principality since 1267 and by Venice, though in 1455 John was forced to exile.

The King of Thessalonica was the ruler of the Kingdom of Thessalonica, one of the crusader states founded in Greece in the aftermath of the Fourth Crusade (1202–1204). The King of Thessalonica was not an independent ruler; the Kingdom of Thessalonica was one of several vassal states created by the crusaders, subservient to the new Latin Empire of Constantinople, which had supplanted the Byzantine Empire.

The kingdom proved to be short-lived, with Thessalonica being captured by Theodore Komnenos Doukas of Epirus in 1224, just twenty years after the kingdom had been founded. The last king, Demetrius of Montferrat, escaped into exile and upon his death ceded the title to Frederick II, Holy Roman Emperor, who some years later ceded it back to Demetrius's family. Their line of titular Kings of Thessalonica ended with the marriage of Yolande of Montferrat to Byzantine emperor Andronikos II Palaiologos in 1284, at which point titular ownership of Thessalonica passed back to the Byzantine emperors.

The Aleramici (also Aleramids) were a Northern Italian princely and royal dynasty of Frankish origin. They ruled over various northwestern Italian principalities in Piedmont and Liguria from the 10th to the 17th century, as well as over the Kingdoms of Jerusalem and Thessalonica from the 12th to 13th centuries.

Considered one of the foremost crusader dynasties, the Aleramids notably extended their influence across the Eastern Mediterranean, thrice appointed as successors to the Eastern Roman Imperial throne (under the title of Caesar), without ever ensuring their effective installation. They nevertheless produced two Imperial consorts, one of which (Irene) effectively ruled over part of the Empire under the title of Augusta. Other females of the dynasty also appear as consort-regents in several European states.