country_of_citizenship sergius i of constantinople
The ___MASK49___ ( Koine and Medieval Greek :    , tr . ) was the post - ___MASK21___ period of the ancient Roman civilization , characterized by government headed by emperors and large territorial holdings around the Mediterranean Sea in Europe , Africa and Asia . The city of Rome was the largest city in the world BC AD , with Constantinople ( New Rome ) becoming the largest around 500 AD , and the Empire ' s populace grew to an estimated 50 to 90 million inhabitants ( roughly 20 % of the world ' s population at the time ). The 500 - year - old republic which preceded it was severely destabilized in a series of civil wars and political conflict , during which Julius Caesar was appointed as perpetual dictator and then assassinated in 44 BC . Civil wars and executions continued , culminating in the victory of Octavian , Caesar ' s adopted son , over Mark Antony and Cleopatra at the Battle of Actium in 31 BC and the annexation of Egypt . Octavian ' s power was then unassailable and in 27 BC the Roman Senate formally granted him overarching power and the new title " Augustus ", effectively marking the end of the ___MASK21___ . The Ecumenical Patriarch (" His Most Divine All - Holiness the Archbishop of Constantinople , New Rome and Ecumenical Patriarch ") is the Archbishop of Constantinople  New Rome and ranks as " primus inter pares " ( first among equals ) among the heads of the several autocephalous churches that make up the Eastern Orthodox Church , and is widely regarded as the representative and spiritual leader of the 300 million Orthodox Christians worldwide . The term " Ecumenical " in the title historically referred to the Ecumene , a Greek designation for the civilised universe , i . e . the ___MASK49___ , and legally stems from Canon 28 of the Council of Chalcedon . Byzantium (" Byzántion ") was an ancient Greek colony on the site that later became Constantinople , and later still Istanbul . Byzantium was colonised by the Greeks from ___MASK40___ in . The Council of Chalcedon ( or ) was a church council held from October 8 to November 1 , AD 451 , at Chalcedon . The Council is numbered as the fourth ecumenical council by the Great Church . A minority of Christians do not agree with the council ' s teachings . Its most important achievement was to issue the Chalcedonian Definition . The Council ' s judgements and definitions regarding the divine marked a significant turning point in the Christological debates . Chalcedon was a city in Bithynia , on the Asian side of the Bosphorus ; today the city it is part of the Republic of ___MASK8___ and is known as Kadköy ( a district of Istanbul ). The ___MASK24___ , also referred to as the Eastern Roman Empire , was the continuation of the Roman Empire in the East during Late Antiquity and the Middle Ages , when its capital city was Constantinople ( modern - day Istanbul , which had been founded as Byzantium ). It survived the fragmentation and fall of the Western Roman Empire in the 5th century AD and continued to exist for an additional thousand years until it fell to the Ottoman Turks in 1453 . During most of its existence , the empire was the most powerful economic , cultural , and military force in Europe . Both " ___MASK24___ " and " Eastern Roman Empire " are historiographical terms created after the end of the realm ; its citizens continued to refer to their empire as the " Roman Empire " ( tr . ), or " Romania ", and to themselves as " Romans ". Constantinople was the capital city of the Roman / ___MASK24___ ( 330  1204 and 1261  1453 ), and also of the brief Latin ( 1204  1261 ), and the later Ottoman ( 1453  1923 ) empires . It was reinaugurated in 324 AD from ancient Byzantium as the new capital of the Roman Empire by Emperor Constantine the Great , after whom it was named , and dedicated on 11 May 330 AD . In Abrahamic religions , the Messiah or Messias is a saviour or liberator of a group of people , more specifically , the ___MASK6___ . Rome is a city and special " comune " ( named " Roma Capitale ") in ___MASK18___ . Rome is the capital of ___MASK18___ and of the Lazio region . With 2 , 870 , 336 residents in , it is also the country ' s largest and most populated " comune " and fourth - most populous city in the European Union by population within city limits . The Metropolitan City of Rome has a population of 4 . 3 million residents . The city is located in the central - western portion of the Italian Peninsula , within Lazio ( Latium ), along the shores of Tiber river . The ___MASK28___ is an independent country geographically located within the city boundaries of Rome , the only existing example of a country within a city : for this reason Rome has been often defined as capital of two states . The ecumene ( US ) or oecumene ( UK " oikoumén ", " inhabited ") was an ancient Greek term for the known world , the inhabited world , or the habitable world . Under the ___MASK49___ , it came to refer to civilization and the secular and religious imperial administration . In present usage , it is used as the noun form of " ecumenical " and describes the Christian Church as a unified whole or the unified modern world civilization . It is also used in cartography to describe a type of world map (" mappa mundi ") used in late Antiquity and the Middle Ages . Christianity is a monotheistic religion based on the life and teachings of Jesus Christ , who serves as the focal point for the religion . It is the world ' s largest religion , with over 2 . 4 billion followers , or 33 % of the global population , known as Christians . Christians believe that Jesus is the Son of God and the savior of humanity whose coming as the Messiah ( the Christ ) was prophesied in the Old Testament . Heraclius (' c . 575  February 11 , 641 ) was the Emperor of the ___MASK24___ from 610 to 641 . Sergius I ( d . 9 December 638 in Constantinople ) was the Ecumenical Patriarch of Constantinople from 610 to 638 . He is most famous for promoting Monothelite Christianity , especially through the Ecthesis . Sergius was born of Syrian Jacobite heritage . He first came to power as Patriarch of Constantinople in 610 . He was also a known supporter of Emperor Heraclius , crowning Heraclius as Emperor himself in 610 . Sergius also provided support to Heraclius throughout his campaign against the Persians . Sergius also played a prominent role in the defense of Constantinople against the combined Avar - Persian - Slavic forces during their invasion of Constantinople in 626 . Sergius '' connections to both political and religious authorities gave him to his influence in both the religious and political communities to further Monothelitism as the primary formula of Christ within the church . This was met with much opposition , especially from that of the Chalcedonian supporters , Maximus the Confessor and Sophronius . In response to their resistance to accept the ideas of Monothelitism , Sergius responded with the Ecthesis , a formula which forbade the idea that the Person of Christ had two energies in favour of the idea that the Person of Christ had two natures that were united by a single will . The Ecthesis was signed by Heraclius in 638 , the same year that Sergius died . The Ecthesis would only be seen as an accepted doctrine for two years ; the death of Pope Honorius I resulted in a significant reduction in Monothelitism support . The Ethesis was condemned in 640 by Pope John IV . Additionally , both Sergius and Pope Honorius I were condemned as heretics by the church in 680 - 681 by the Third Council of Constantinople . The Ecthesis is a letter published in 638 CE by the Byzantine emperor Heraclius which defined monotheletism as the official imperial form of Christianity . Primus inter pares (" prtos metax ísn ") is a Latin phrase meaning first among equals . It is typically used as an honorary title for those who are formally equal to other members of their group but are accorded unofficial respect , traditionally owing to their seniority in office . Historically , the " princeps senatus " of the Roman Senate was such a figure and initially only bore the distinction that he was allowed to speak first during debate . Also , Constantine the Great was given the role of " primus inter pares ". However , the term is also often used ironically or self - deprecatingly by leaders with much higher status as a form of respect , camaraderie , or propaganda . After the fall of the Republic , Roman emperors initially referred to themselves only as " princeps " despite having power of life and death over their " fellow citizens ". Various modern figures such as the Chair of the Federal Reserve , the prime minister of parliamentary regimes , the Federal President of ___MASK20___ , the Chief Justice of the United States , and the Ecumenical Patriarch of the Eastern Orthodox Church fall under both senses : bearing higher status and various additional powers while remaining still merely equal to their peers in important senses .