Boniface I, Marquis of Montferrat in the context of King of Thessalonica

Michael I Komnenos Doukas, Latinized as Comnenus Ducas (Greek: Μιχαήλ Κομνηνός Δούκας, romanized: Mikhaēl Komnēnos Doukas), and in modern sources often recorded as Michael I Angelos, a name he never used, was the founder and first ruler of the Despotate of Epirus from c. 1205 until his assassination in 1214/15.

Born c. 1170, Michael was a descendant of Alexios I Komnenos and a cousin of emperors Isaac II Angelos and Alexios III Angelos. He began his public career in 1190, as a hostage to the Third Crusade, and went on to serve as governor of the province of Mylasa and Melanoudion in the 1190s and again in c. 1200/01. During the latter tenure he rebelled against Alexios III but was defeated and forced to flee to the Seljuk Turks. In the aftermath of the sack of Constantinople by the Fourth Crusade in 1204, he attached himself to Boniface of Montferrat. Soon, however, he abandoned the Crusader leader and went to Epirus, where he established himself as ruler, apparently through marriage with the daughter or widow of a local magnate.

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 Theme of Hellas (Greek: θέμα Ἑλλάδος, Thema Hellados) was a Byzantine military-civilian province (thema, theme) located in southern Greece. The theme encompassed parts of Central Greece, Thessaly and, until c. 800, the Peloponnese peninsula. It was established in the late 7th century, and was broken up into smaller districts in the late 11th/early 12th century. The theme fell to the Crusader army led by Boniface of Montferrat in 1205.

Year 1201 (MCCI) was a common year starting on Monday of the Julian calendar.