At Christmas 1196, Holy Roman Emperor Henry VI attempted to force Alexios III to pay him a tribute of 5, 000 pounds ( later negotiated down to 1, 600 pounds ) of gold or face invasion.

In the east the Empire was overrun by the Seljuk Turks ; from the north Bulgarians and Vlachs descended unchecked to ravage the plains of Macedonia and Thrace, and Kaloyan of Bulgaria annexed several important cities, while Alexios squandered the public treasure on his palaces and gardens and attempted to deal with the crisis through diplomatic means.

Trying to escape Boniface's " protection ", Alexios III attempted to seek shelter with Michael I Komnenos Doukas, the ruler of Epirus, in 1205.

His participation in the attempted usurpation of John Komnenos the Fat in 1200 had caused him to be imprisoned until the accession of Isaac II Angelos, who was restored to the throne after having been deposed and imprisoned by his brother Alexios III, and his son Alexios IV Angelos, who were placed on the throne by the intervention of the Fourth Crusade in July 1203.

In 1187, Alexios Branas, the victor over the Normans, was sent against the Bulgarians but turned his arms against his master, and attempted to seize Constantinople, only to be defeated and slain by Isaac's brother-in-law Conrad of Montferrat.

He then attempted to defeat his uncle Alexios III, who remained in control of Thrace.

Alexios IV attempted to reach a reconciliation with the Crusaders, entrusting the anti-western courtier Alexios Doukas Murzuphlus with a mission to gain Crusader support.

Once at the pass Manuel decided to attack, despite the danger from further ambushes, and also despite the fact that he could have attempted to bring the Turks out of their positions to fight them on the nearby plain of Philomelion, the site of an earlier victory won by his grandfather Alexios.

Isaac now traveled to the Sultanate of Rum, where he attempted to gain support against the new Byzantine Emperor Alexios III Angelos ( 1195 – 1203 ).

The united forces met little resistance in the eastern Serbian lands-the Greek squadrons were fighting among themselves as the local Byzantine commanders: Alexios Brannes supported the new Emperor, while Andronicus Lapardes opposed him-and deserted the Imperial Army, going onto adventures on his own.

Soon Alexios III was threatened by a new and yet more formidable danger.

Later, however, Alexios III arranged for his new son-in-law to be ambushed and blinded, making him ineligible for the imperial throne.

The next day, April 12, 1034, the couple summoned the Patriarch Alexios I to officiate in the coronation of the new emperor.

After Manzikert, the Byzantine government sent a new army to contain the Seljuk Turks under Isaac Komnenos, a brother of the future emperor Alexios I Komnenos, but this army was defeated and its commander captured in 1073.

A new army under Alexios Komnenos, reinforced by Seljuk troops sent by Malik Shah I, finally defeated the mercenaries and captured John Doukas in 1074.

Ascending as Alexios III Angelos, the new emperor had his brother blinded ( a traditional punishment for treason ) and imprisoned.

The son, who was distinguished for his learning, personal beauty, and engaging qualities, gained the favour of Alexios I and the hand of his daughter Anna Komnene, receiving the titles of Caesar and panhypersebastos ( one of the new dignities introduced by Alexios ).

Emperor Alexios I Komnenos ( 1081 – 1118 ) established a new military force from the ground up, which was directly responsible for transforming the aging Byzantine Empire from one of the weakest periods in its existence into a major economic and military power, akin to its existence during the golden age of Justinian I.

In 1107, having organized a new army for his planned crusade against the Muslims in Syria, Bohemond instead launched into open warfare against Alexios, crossing the Adriatic to besiege Dyrrhachium, the westernmost city of the Empire.

Yet, through a combination of skill, determination and years of campaigning, Alexios, John and Manuel Komnenos managed to restore the power of the Byzantine Empire by constructing a new army from scratch.

The new Emperor, Alexios I Komnenos, appointed him " megas domestikos of All the West " and gave him many more properties in the Balkans.

Consequently in 1092, Emperor Alexios I Komnenos ( r. 1081 – 1118 ) undertook a drastic overhaul of the Byzantine coinage system and introduced a new gold coin, the hyperpyron ( meaning " super-refined ").

The new emperor, Alexios I Komnenos ( 1081 – 1118 ), was forced to call upon the assistance of the Venetians, who in the 1070s had already asserted their control of the Adriatic and Dalmatia against the Normans.

* 1203 – Isaac II Angelos, restored Eastern Roman Emperor, declares his son Alexios IV Angelos co-emperor after pressure from the forces of the Fourth Crusade.

Alexios I Komnenos, Latinized as Alexius I Comnenus (, 1056 – 15 August 1118 — note that some sources list his date of birth as 1048 ), was Byzantine emperor from 1081 to 1118, and although he was not the founder of the Komnenian dynasty, it was during his reign that the Komnenos family came to full power.

Alexios became estranged from Maria, who was stripped of her imperial title and retired to a monastery, and Constantine Doukas was deprived of his status as co-emperor.

Next, Alexios had to deal with disturbances in Thrace, where the heretical sects of the Bogomils and the Paulicians revolted and made common cause with the Pechenegs from beyond the Danube.

Alexios used the opportunity of meeting the crusader leaders separately as they arrived and extracting from them oaths of homage and the promise to turn over conquered lands to the Byzantine Empire.

Apart from all of his external enemies, a host of rebels also sought to overthrow Alexios from the imperial throne, thereby posing another major threat to his reign.

She excluded her young son from power, entrusting it instead to Alexios the prōtosebastos ( a cousin of Alexios II ), who was popularly believed to be her lover.

Alexios III Angelos () ( c. 1153 – 1211 ) was Byzantine Emperor from 1195 to 1203.

By 1190 Alexios Angelos had returned to the court of his younger brother, from whom he received the elevated title of sebastokratōr.

Alexios captured Isaac at Stagira in Macedonia, put out his eyes, and thenceforth kept him a close prisoner, though he had been redeemed by him from captivity at Antioch and loaded with honours.

Alexios IV Angelos, the son of the deposed Isaac II, had recently escaped from Constantinople and now appealed to the crusaders, promising to end the schism of East and West, to pay for their transport, and to provide military support to the crusaders if they helped him to depose his uncle and sit on his father's throne.

Alexios III finally took action, and led 17 divisions from the St. Romanus Gate, vastly outnumbering the crusaders.

Isaac II, drawn from his prison and robed once more in the imperial purple, received his son, Alexios IV, in state.

Later Alexios V was blinded and deserted by his father-in-law, who fled from the crusaders into Thessaly.

By the beginning of 1204, Isaac II and Alexios IV had inspired little confidence among the people of Constantinople in their efforts to defend the city from the Latins and Venetians, who were restless and rioted when the money and aid promised by Alexios IV was not forthcoming.

When the populace rebelled in late January 1204, the emperors barricaded themselves in the palace and entrusted Alexios Doukas with a mission to seek help from the crusaders.

Brought back to Constantinople, Alexios V was condemned to death for treason against Alexios IV, and was thrown from the top of the Column of Theodosius.

Many historians maintain that the main concern of Pope Urban II, when calling for the First Crusade, was the threat to Constantinople from the Turkish invasion of Asia Minor in response to the appeal of Emperor Alexios I Komnenos.