Theodore I Laskaris in the context of "Latins (Middle Ages)"

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.

Béla IV (1206 – 3 May 1270) was King of Hungary and Croatia between 1235 and 1270, and Duke of Styria from 1254 to 1258. As the oldest son of King Andrew II, he was crowned upon the initiative of a group of influential noblemen in his father's lifetime in 1214. His father, who strongly opposed Béla's coronation, refused to give him a province to rule until 1220. In this year, Béla was appointed Duke of Slavonia, also with jurisdiction in Croatia and Dalmatia. Around the same time, Béla married Maria, a daughter of Theodore I Laskaris, Emperor of Nicaea. From 1226, he governed Transylvania as duke. He supported Christian missions among the pagan Cumans who dwelled in the plains to the east of his province. Some Cuman chieftains acknowledged his suzerainty and he adopted the title of King of Cumania in 1233. King Andrew died on 21 September 1235 and Béla succeeded him. He attempted to restore royal authority, which had diminished under his father. For this purpose, he revised his predecessors' land grants and reclaimed former royal estates, causing discontent among the noblemen and the prelates.

The Mongols invaded Hungary and annihilated Béla's army in the Battle of Mohi on 11 April 1241. He escaped from the battlefield, but a Mongol detachment chased him from town to town as far as Trogir on the coast of the Adriatic Sea. Although he survived the invasion, the Mongols devastated the country before their unexpected withdrawal in March 1242. Béla introduced radical reforms in order to prepare his kingdom for a second Mongol invasion. He allowed the barons and the prelates to erect stone fortresses and to set up their private armed forces. He promoted the development of fortified towns. During his reign, thousands of colonists arrived from the Holy Roman Empire, Poland and other neighboring regions to settle in the depopulated lands. Béla's efforts to rebuild his devastated country won him the epithet of "second founder of the state" (Hungarian: második honalapító).

The House of Laskaris (Greek: Λάσκαρις (Láskaris), later Λάσκαρης; feminine form Laskarina; Greek: Λασκαρίνα), Latinized as Lascaris, was a Byzantine Greek noble family which rose to prominence during the late Byzantine period. The members of the family formed the ruling dynasty of the Empire of Nicaea, a Byzantine rump state that existed from the 1204 sack of Constantinople by the Fourth Crusade until the restoration of the Empire under the Palaeologan dynasty in 1261.

Upon the sack of the Byzantine capital by the Crusaders, Alexios V Doukas was overthrown and the Latin Empire was established in most of his former lands. Byzantine nobility would flee the Latin territories and establish the three independent Greek states that rivaled the Crusaders. After a successful resistance in Asia Minor, Theodore I Laskaris founded the Empire of Nicaea and laid claims to the Byzantine throne, along with the Angelos family of Epirus and the Komnenoi of Trebizond. The Byzantine Greek population of Asia Minor sought refuge to Theodore's empire, which gradually acquired control over much of western Anatolia. The empire was further strengthened after the military victories of Theodore's successor, John III Vatatzes. John's son, Theodore II Laskaris, maintained the empire's strength until the throne was passed to his underage son, John IV Laskaris. In 1259 John fell victim to an aristocratic conspiracy which managed to establish Michael Palaiologos as his regent and co-emperor.

Maria Laskarina (Greek: Μαρία Λασκαρίνα, romanized: María Laskarina, Hungarian: Laszkarisz Mária, c. 1206 – 24 June or 16 July 1270) was a Greek Queen consort of Hungary by marriage to King Béla IV of Hungary. She was the daughter of Theodore I Laskaris and Anna Komnena Angelina.

Theodore II Doukas Laskaris or Ducas Lascaris (Greek: Θεόδωρος Δούκας Λάσκαρις, romanized: Theodōros Doúkās Láskaris; November 1221/1222 – 16 August 1258) was Emperor of Nicaea from 1254 to 1258. He was the only child of Emperor John III Doukas Vatatzes and Empress Irene Laskarina. His mother was the eldest daughter of Theodore I Laskaris, who had established the Empire of Nicaea as a successor state to the Byzantine Empire in Asia Minor after the crusaders captured the Byzantine capital, Constantinople, during the Fourth Crusade in 1204. Theodore received an excellent education from two renowned scholars, Nikephoros Blemmydes and George Akropolites. He made friends with young intellectuals, especially with a page of low birth, George Mouzalon. Theodore began to write treatises on theological, historical and philosophical themes in his youth.

Emperor John III arranged for Theodore to marry Elena Asenina in 1235, to forge an alliance with her father, Ivan Asen II, Emperor of Bulgaria, against the Latin Empire of Constantinople. According to Theodore himself, their marriage was happy, and they had five or six children. From 1241, Theodore acted as his father's lieutenant in Asia Minor during his frequent military campaigns in the Balkan Peninsula. From around 1242, he was his father's co-ruler, but was not crowned as co-emperor. During this period, his relationship with some prominent aristocrats, particularly Theodore Philes and Michael Palaiologos, grew tense.