In 647 an army of 40, 000 Arabs, led by Abdullah ibn Saad had come to take Libya from the Byzantines and Berbers.

The first battles of the campaign ended in defeat for the Byzantines ; the Persian army fought their way to the Bosphorus.

The Bulgarians come to the aide of the Byzantines and defeat the army of invading Arabs, thus completely neutralizing their advance towards Europe.

* September – The Byzantines are defeated by an Abbasid army in the Battle of Kopidnados.

They defeat the Byzantines, Mundus is killed during the fightings at Salona, and the Byzantine army withdraws.

The Byzantines counter-attack and seize Germanikeia, defeating an army from Tarsus, and the raiding as far south as Antioch.

Gathering his forces at Mosynopolis, the emperor waited for the Bulgarian army ; the military success of the Byzantines was aided by internal dissension among the Bulgarians and eventually their leaders were defeated and captured.

The underpaid army tended to mutiny, and the Byzantines lost Bari, their last possession in Italy, to the Normans of Robert Guiscard in 1071.

The Byzantine army pursued the Sassanians into the town but to Byzantines ' dismay, they walked into an ambush and were completely routed.

Petar was recognized by the Bulgars, now the greatest power in the Balkans, although the peace was not to last ; the Byzantines had sent an envoy to Serbia promising greater independence in return for Petar leading an army against the Bulgars.

By 647, Muawiyah had built a Syrian army strong enough to repel a Byzantine attack and, in subsequent years, to take the offensive against the Byzantines in campaigns that resulted in the capture of Cyprus ( 649 ) and Rhodes ( 654 ) and a devastating defeat of the Byzantine navy off the coast of Lycia ( 655 ).

At first, the Byzantines, established in Apulia, had tried to buy off the Normans and press them into service within their own largely mercenary army ; since the Normans were famous for their avarice.

Myriokephalon, although a significant defeat for the Byzantines, did not materially affect the capabilities of the Byzantine army.

The assembled army consisted of contingents of Byzantines, Slavs, Franks, Georgians, Armenians and Christian Arabs.

In 1094, Kilij Arslan received a letter from Alexius suggesting that the Chaka sought to target him to move onto the Byzantines, thereupon Kilij Arslan marched with an army to Smyrna, Chaka ’ s capital, and invited his father-in-law to a banquet in his tent where he slew him while he was intoxicated.

To face this threat, Samuel gathered a large army to face the Byzantines, some claiming it numbered as many as 45, 000 soldiers.

The Nicaeans continued some aspects of the Komnenian army, but without the resources available to the Komnenian emperors the Nicaean Byzantines could not match the numbers, nor the quality, of the armies that the emperor Manuel and his predecessors had fielded.

Informed by the local Byzantine governor of William's actions, Michael VIII sent an army under the command of his half-brother, Constantine, against William, but the expedition was unsuccessful, the Byzantines first being routed at the Battle of Prinitza in 1263 and then, after Constantine's return to Constantinople, suffering a heavy defeat at the Battle of Makryplagi in 1264.

The Byzantines attributed it to a sign that the Christian God would soon come and destroy the conquering Muslim army.

This army was assembled in the mountain passes to intercept the Byzantines as they return to Constantinople.

Simeon I's army defeating the Byzantines, led by Procopius Crenites and Curtacius the Armenian in Macedonia.

Decades later, Leo the Deacon would write that " piles of bones can still be seen today at the river Acheloos, where the fleeing army of the Byzantines was then infamously slain ".< ref > Leo the Deacon, History, p. 124 < sub > 10 – 12 </ sub >.

They carried rumors of Heraclius ' preparations and the existence of an enormous army said to number anywhere from 40, 000 to several 100, 000 besides the Lakhm, Judham and other Arab tribes allied to the Byzantines.

After arriving at Tabouk and camping there, the Muhammad's army was prepared to face the Byzantines.

Umar, allegedly aware of this alliance, capitalized on this failure: not wanting to risk a battle with two great powers simultaneously, he quickly moved to reinforce the Muslim army at Yarmouk to engage and defeat the Byzantines.

In Maghreb ( western North Africa ) in 686 a force led by Zuhayr ibn Qais won the Battle of Mamma over Byzantines and Berbers led by Kusaila, on the Qairawan plain, and re-took Ifriqiya and its capital Kairouan.

The Byzantines withdrew from all of Africa except Ceuta.

Paul K. Davis writes, " With this victory, the Byzantines regained control of North Africa for the Eastern Roman Empire.

A very strategic river in North Africa, it was fought over and settled many times in history by the Berbers, Phoenicians, Punics, Romans, Vandals, Byzantines, Arabs, and the Ottomans.

The Justinian edict of persecution for North Africa, issued after the Vandal rule had been overthrown and Mauretania had come under the dominion of the Byzantines ( 534 ), was directed against the Jews as well as the Arians, the Donatists, and other dissenters.

Following the loss of the Levant and later Africa, the Mediterranean Sea was transformed from a " Roman lake " into a battleground between Byzantines and Arabs.

The Byzantines were unable to respond effectively to the Muslim advance in Africa, because the two decades between 695 and 715 were a period of great domestic turmoil.

With the Lombard invasion of Italy it was annexed to the Duchy of Benevento, until it was finally destroyed by the Byzantines of Constans II in 663, reducing to a small hamlet known as Quintodecimo ( referring to its distance of 15 miles from Benevento ).

Bursa became the first major capital city of the early Ottoman Empire following its capture from the Byzantines in 1326.

Kallinikos ' development of Greek fire came at a critical moment in the Byzantine Empire's history: weakened by its long wars with Sassanid Persia, the Byzantines had been unable to effectively resist the onslaught of the Muslim conquests.

Syria was dominated by many peoples in its history, including the Sumerians, Akkadians, Assyrians, Chaldeans, Canaanites, Arameans, Hattians, Babylonians, Persians, Greeks, Romans, Nabataeans, Byzantines, Arabs, Crusaders, Ottomans, and French.

Though the Byzantines recovered control of the ravaged city a half century later, the Byzantine Empire was terminally weakened, and existed as a ghost of its old self until Sultan Mehmet The Conqueror took the city in 1453.

The Byzantines rebuild its walls and reclaim the province.

The slaves were mostly captured by Venice from Dalmatia, the Holy Roman Empire from what is now Prussia and Poland, and the Byzantines from elsewhere in the Balkans, and were generally destined for other parts of the Byzantine Empire and ( most frequently ) the Muslim states surrounding the Mediterranean: the Abbasid Caliphate, the Umayyad Caliphate of Córdoba, the Emirate of Sicily, and the Fatimid Caliphate ( which relied on Slavs purchased at the Bari market for its legions of Sakalaba Mamluks ).

Basil spent three months in Syria, during which the Byzantines raided as far as Baalbek, took and garrisoned Shaizar and captured three minor forts in its vicinity ( Abu-qubais, Masyath, ' Arqah ), and sacked Rafaniya.

In constant fear of attack from the Normans in the south of Italy, the Byzantines turned in desperation to the Normans own spiritual chief, Pope Leo IX and, according to William of Apulia, begged him " to liberate Italy that now lacks its freedom and to force that wicked people, who are pressing Apulia under their yoke, to leave.

When Totila left to fight the Byzantines in Lucania, south of Naples, Belisarius retook Rome and rebuilt its fortifications.

According to some scholars, the Blue-Green rivalry contributed to the conditions that underlay the rise of Islam, while factional enmities were exploited by the Sassanid Empire in its conflicts with the Byzantines during the century preceding Islam's advent.

In 1031 Edessa was given up to the Byzantines under George Maniakes by its Arab governor.

Enamel was at its most important in European art history in the Middle Ages, beginning with the Late Romans and then the Byzantines who began to use cloisonné enamel in imitation of cloisonné inlays of precious stones.

When Charlemagne was proclaimed Emperor of the Holy Roman Empire the Pope broke its political relation with Byzantines and was naturally supported by the Franks.

Simeon's successful campaigns against the Byzantines, Magyars and Serbs led Bulgaria to its greatest territorial expansion ever, making it the most powerful state in contemporary Eastern Europe.

It was recaptured by the Byzantines around 1235 and stayed in its borders until first half of the 14th century.

The Byzantines, upon constructing the new church, placed the central octagon directly on top of the walls of St. Peter's house with the aim of preserving its exact location, although none of the original house was visible any longer, as the walls had been torn down and the floor covered in mosaics.

Because of its position on the frontier, the city was repeatedly fought over and was recaptured from time to time by the Byzantines: it was besieged in vain by the Byzantine troops of John I Tzimisces in 964 but was taken the following year after a long and difficult siege by Nicephorus Phocas.

Its garrison resisted for 37 days, but the siege engines of the Byzantines battered down its walls, and the city was forced to surrender.

The city, which was called Drobeta by the Romans, took its name of Turnu Severin ( meaning the Tower of Severus ) from a tower on the north bank of the Danube built by the Byzantines.

The weakened Byzantine Empire no longer possessed the resources to defeat Murad on its own, and concerted action on the part of the Byzantines, often divided by civil war, was impossible.

The Byzantines wanted the region, for if they secured its passes, they could prevent Persian raids on the border areas of Lazica.

The outer wall was a formidable defensive edifice in its own right: in the sieges of 1422 and 1453, the Byzantines and their allies, being too few to hold both lines of wall, concentrated on the defence of the outer wall.