The presence of the Latin Crusader states almost immediately led to war with the Byzantine successor states and with the Bulgarian Empire. The Nicaean Empire eventually recovered Constantinople and restored the Byzantine Empire in 1261. The Fourth Crusade is considered to have solidified the East–West Schism.

Alexius I Comnenus, also spelled Alexios I Komnenos, (born 1057, Constantinople, Byzantine Empire [now Istanbul, Turkey]—died August 15, 1118), Byzantine emperor (1081–1118) at the time of the First Crusade who founded the Comnenian dynasty and partially restored the strength of the empire after its defeats by the …

Wars against the Normans, Pechenegs, and Tzachas The thirty-seven year reign of Alexios was full of struggle. At the outset he faced the formidable attack of the Normans, led by Robert Guiscard and his son Bohemund, who took Dyrrhachium and Corfu and laid siege to Larissa in Thessaly (see Battle of Dyrrhachium).

The Empire gave rise to the Eastern Orthodox Church. Byzantium was almost always a Christian empire, but over the centuries its Greek-speaking church developed distinct liturgical differences from the Catholic, Latin-speaking church in the West.

The fall of Constantinople

Latin was used throughout the Roman Empire, but it shared space with a host of other languages and dialects, including Greek, Oscan and Etruscan, which give us a unique perspective on the ancient world.

Little is known about Greek Fire because it was such a closely guarded secret; eventually the Byzantine Empire realised no one remembered how to make it! The water and Greek fire would mix when the pot smashed and would combust.

It was invented during the reign of Constantine IV Pogonatus (668–685) by Callinicus of Heliopolis, a Greek-speaking Jewish refugee who had fled the Arab conquest of Syria. The substance could be thrown in pots or discharged from tubes; it apparently caught fire spontaneously and could not be extinguished with water.

In the AD 670s, the Byzantines repelled an Arab fleet attacking Constantinople with siphons mounted to their ships – the beginning of its dominance in its arsenal, which helped the empire survive until the 15th century. But then Greek fire disappeared.

Greek fire was a flaming mixture fired from the ships of the Byzantine empire from the 7th century. The fire would cling to flesh and was impossible to extinguish with water. This deadly concoction was created by a family of chemists and engineers from Constantinople, and the secret recipe died with them.