Sviatoslav or Svyatoslav I Igorevich was Prince of Kiev from 945 until his death in 972. He is known for his persistent campaigns in the east and south, which precipitated the collapse of two great powers in Eastern Europe, Khazaria and the First Bulgarian Empire. He conquered numerous East Slavic tribes, defeated the Alans and attacked the Volga Bulgars, and at times was allied with the Pechenegs and Magyars (Hungarians).
Michael III, also known as Michael the Drunkard, was Byzantine emperor from 842 to 867. Michael III was the third and traditionally last member of the Amorian dynasty. He was given the disparaging epithet the Drunkard by the hostile historians of the succeeding Macedonian dynasty, but modern historical research has rehabilitated his reputation to some extent, demonstrating the vital role his reign played in the resurgence of Byzantine power in the 9th century. He was also the youngest person to bear the imperial title, as well as the youngest to succeed as senior emperor.
Oleg, also known as Oleg the Wise, was a Varangian prince of the Rus' who became prince of Kiev, and laid the foundations of the Kievan Rus' state.
The Varangian Guard was an elite unit of the Byzantine army from the tenth to the fourteenth century who served as personal bodyguards to the Byzantine emperors. The Varangian Guard was known for being primarily composed of recruits from Northern Europe, including mainly Norsemen from Scandinavia but also Anglo-Saxons from England. The recruitment of distant foreigners from outside Byzantium to serve as the emperor's personal guard was pursued as a deliberate policy, as they lacked local political loyalties and could be counted upon to suppress revolts by disloyal Byzantine factions.
Constantinople was besieged by the Arabs in 674–678, in what was the first culmination of the Umayyad Caliphate's expansionist strategy against the Byzantine Empire. Caliph Mu'awiya I, who had emerged in 661 as the ruler of the Muslim Arab empire following a civil war, renewed aggressive warfare against Byzantium after a lapse of some years and hoped to deliver a lethal blow by capturing the Byzantine capital of Constantinople.
The Caspian expeditions of the Rus' were military raids undertaken by the Rus' between the late 9th century and c. 1041 on the Caspian Sea shores, of what are nowadays Iran, Dagestan, and Azerbaijan. Initially, the Rus' appeared in Serkland in the 9th century travelling as merchants along the Volga trade route, selling furs, honey, and slaves. The first small-scale Viking raids took place in the late 9th and early 10th century. The Rus' undertook the first large-scale expedition in 913; having arrived on 500 ships, they pillaged in the Gorgan region, in the territory of present-day Iran, and more to the west, in Gilan and Mazandaran, taking slaves and goods. On their return, the northern raiders were attacked and defeated by the Khazars in the Volga Delta, and those who escaped were killed by the local tribes in the middle Volga.
The siege of Constantinople in 860 was the only major military expedition of the Rus' people recorded in Byzantine and western European sources. The casus belli was the construction of the fortress Sarkel by Byzantine engineers, restricting the Rus' trade route along the Don River in favour of the Khazars. Accounts vary, with discrepancies between contemporary and later sources, and the outcome is unknown in detail.
The final Rus'–Byzantine War was, in essence, an unsuccessful naval raid against Constantinople instigated by Yaroslav the Wise and led by his eldest son, Vladimir of Novgorod, in 1043.
The Rus'–Byzantine War of 941 took place during the reign of Igor of Kiev. The first naval attack was driven off and followed by another, successful offensive in 944. The outcome was the Rus'–Byzantine Treaty of 945.
According to the Primary Chronicle, the first Rus'–Byzantine Treaty was concluded in 907 as a result of Oleg's raid against Constantinople. Scholars generally consider this document as preliminary to the Rus'–Byzantine Treaty of 911.
The Rus'–Byzantine Treaty of 911 is the most comprehensive and detailed treaty which was allegedly concluded between the Byzantine Empire and Kievan Rus' in the early 10th century. It was preceded by the preliminary treaty of 907. It is considered the earliest written source of Kievan Rus' law. The text of this treaty is only found in the Primary Chronicle (PVL), and its authenticity is therefore difficult to establish.
The Byzantine Empireunder the Macedonian dynasty underwent a revival during the late 9th, 10th, and early 11th centuries. Under the Macedonian emperors, the empire gained control over the Adriatic Sea, Southern Italy, and all of the territory of the Tsar Samuil of Bulgaria. The Macedonian dynasty was characterised by a cultural revival in spheres such as philosophy and the arts, and has been dubbed the "Golden Age" of Byzantium.
The Byzantine Empire's history is generally periodised from late antiquity until the Fall of Constantinople in 1453 AD. From the 3rd to 6th centuries, the Greek East and Latin West of the Roman Empire gradually diverged, marked by Diocletian's formal partition of its administration in 285, the establishment of an eastern capital in Constantinople by Constantine I in 330, and the adoption of Christianity as the state religion under Theodosius I, with others such as Roman polytheism being proscribed. Under the reign of Heraclius, the Empire's military and administration were restructured and adopted Greek for official use instead of Latin. While there was an unbroken continuity in administration and other features of Roman society, historians have often distinguished the Byzantine epoch from earlier eras in Roman history for reasons including the imperial seat moving from Rome to Constantinople and the predominance of Greek instead of Latin.
Kievan Rus', also known as Kyivan Rus', was the first East Slavic state and later an amalgam of principalities in Eastern Europe from the late 9th to the mid-13th century. Encompassing a variety of polities and peoples, including East Slavic, Norse, and Finnic, it was ruled by the Rurik dynasty, founded by the Varangian prince Rurik. The name was coined by Russian historians in the 19th century to describe the period when Kiev was at the center. At its greatest extent in the mid-11th century, Kievan Rus' stretched from the White Sea in the north to the Black Sea in the south and from the headwaters of the Vistula in the west to the Taman Peninsula in the east, uniting the East Slavic tribes.
The Varangians were Viking conquerors, traders and settlers, mostly from present-day Sweden, who settled in the territories of present-day Belarus, Russia and Ukraine from the 8th and 9th centuries and established the state of Kievan Rus' as well as the principalities of Polotsk and Turov. They also formed the Byzantine Varangian Guard.
The Emirate of Crete was an Islamic state that existed on the Mediterranean island of Crete from the late 820s to the reconquest of the island by the Byzantine Empire in 961. Although the emirate recognized the suzerainty of the Abbasid Caliphate and maintained close ties with Tulunid Egypt, it was de facto independent.
Sviatoslav's invasion of Bulgaria refers to a conflict beginning in 967/968 and ending in 971, carried out in the eastern Balkans, and involving the Kievan Rus', Bulgaria, and the Byzantine Empire. The Byzantines encouraged the Rus' ruler Sviatoslav to attack Bulgaria, leading to the defeat of the Bulgarian forces and the occupation of the northern and north-eastern part of the country by the Rus' for the following two years. The allies then turned against each other, and the ensuing military confrontation ended with a Byzantine victory. The Rus' withdrew and eastern Bulgaria was incorporated into the Byzantine Empire.
The Byzantine–Bulgarian war of 913–927 was fought between the Bulgarian Empire and the Byzantine Empire for more than a decade. Although the war was provoked by the Byzantine emperor Alexander's decision to discontinue paying an annual tribute to Bulgaria, the military and ideological initiative was held by Simeon I of Bulgaria, who demanded to be recognized as Tsar and made it clear that he aimed to conquer not only Constantinople but the rest of the Byzantine Empire, as well.
The foreign relations of the Eastern Roman Empire were conducted by the emperor. Preferring diplomacy over war, the emperor would use alliances, treaty's and diplomatic tactics to achieve goals. Military confrontations also occurred, with Dimitri Obolensky calling it as a form of "defensive imperialism". The conduct of its foreign relations is a large factor to the Empire's longevity of 1,123 years.
