The French house, a Capetian cadet branch, that supplied the last emperors of the Latin Empire of Constantinople — Peter, Robert, and Baldwin II.
The house took its name from the lordship of Courtenay in the Gâtinais, south of Paris. Its decisive rise came when the heiress of Courtenay married Peter, a younger son of King Louis VI of France, so that the ruling line of the house descended from the Capetian kings — a royal cadet branch, though one without a great territorial base of its own. A separate branch of the family had earlier held the crusader county of Edessa in the East.
That combination of royal blood and crusading connection drew the Courtenays into the affairs of the Latin East created by the Fourth Crusade.
When the Latin Empire of Constantinople, founded after the Fourth Crusade’s sack of the city in 1204, lost its emperors of the house of Flanders-Hainaut, the crown passed by marriage to Peter of Courtenay, who was elected emperor in 1216. Peter never reached his capital: crowned at Rome, he was captured in the Balkans by the ruler of Epirus while marching east, and died in captivity.
His widow and then his sons ruled at Constantinople. Robert of Courtenay presided over a shrinking, impoverished empire hemmed in by the Greek successor states, and the last emperor, Baldwin II, spent his reign pawning relics and touring Europe begging for aid.
In 1261 the Byzantines of Nicaea, under Michael VIII Palaiologos, retook Constantinople almost without a fight while its defenders were away, and Baldwin II fled to the West. The Latin Empire was extinguished after little more than half a century, and the Courtenay emperors and their heirs kept only an empty title.
The house is remembered as the last dynasty of that short-lived Latin state — a Capetian offshoot whose brush with an imperial crown ended in exile, even as the wider Courtenay family endured among the nobility of France and England.