The Rus' people had probably dominated what is now northwestern Russia since the 8th century. In the early ninth they became loosely organized under the Rus' Khaganate, which may be regarded as a predecessor state to the Kievan Rus'. According to the Primary Chronicle, the earliest chronicle of Kievan Rus′, a Varangian (Viking) named Rurik first established himself in Novgorod, located in modern Russia (he was selected as common ruler by several Slavic and Finno-Ugric tribes) in about 860 before moving south and extending his authority to Kiev, the capital of modern day Ukraine. The chronicle cites him as the progenitor of the Rurik Dynasty. The Primary Chronicle says:
In the year 6367 (859): Varangians from over the sea had tribute from Chuds, Slavs, Merias, Veses, Krivichs...
In the year 6370 (862): [They] [d]rove the Varangians back beyond the sea, refused to pay them tribute, and set out to govern themselves. But there was no law among them, and tribe rose against tribe. Discord thus ensued among them, and they began to war one against the other. They said to themselves, "Let us seek a prince who may rule over us, and judge us according to custom." Thus they went overseas to the Varangians, to the Rus. These particular Varangians were called Rus, just as some are called Swedes, and others Normans and Angles, and still others Goths [Gotlanders], for they were thus named. The Chuds, the Slavs, the Krivichs and the Ves then said to the Rus, "Our land is great and rich, but there is no order in it. Come reign as princes, rule over us". Three brothers, with their kinfolk, volunteered. They took with them all the Rus and came.
These Varangians first settled in Ladoga, then moved southward to Novgorod eventually reaching Kiev, finally putting an end to the Khazars' collecting tribute from Kievans. The so-called Kievan Rus was founded by prince Oleg (Helgu in Khazarian records) about 880. During the next 35 years, Oleg and his warriors subdued the various Eastern Slavic and Finnic tribes. In 907, Oleg led an attack against Constantinople, and in 911 he signed a commercial treaty with the Byzantine Empire as an equal partner. The new Kievan state prospered because it had an abundant supply of furs, beeswax, and honey for export and because it controlled three main trade routes of Eastern Europe: the Volga trade route from the Baltic Sea to the Orient, the Dnieper trade route from the Baltic Sea to the Black Sea, and the trade route from the Khazars to the Germans.
Given the postulated pro-Scandinavian bias of the Rus' Primary Chronicle, some Slavic historians have debated the role of the Varangians in the establishment of Kievan Rus′ (see Rus′). By the reign of Sviatoslav I of Kiev (r. 945-972) Kievan rulers had adopted Slavic religion and names, but their druzhina still consisted primarily of Scandinavians. Sviatoslav's military conquests were astonishing: he dealt lethal blows to two of his strongest neighbours, Khazaria and the Bulgarian Empire, which collapsed soon after his raids.
From the 9th century, the Pecheneg nomads started an uneasy relationship with Kievan Rus. For more than two centuries they launched random raids into the lands of Rus, which sometimes escalated into full-scale wars (like the 920 war on the Pechenegs by Igor of Kiev reported in the Primary Chronicle), but there were also temporary military alliances (e.g. 943 Byzantine campaign by Igor). In 968, the Pechenegs attacked and then besieged the city of Kiev.
The region of Kiev dominated the state of Kievan Rus′ for the next two centuries. The grand prince (velikiy kniaz') of Kiev controlled the lands around the city, and his theoretically subordinate relatives ruled in other cities and paid him tribute. The zenith of the state's power came during the reigns of Prince Vladimir (Vladimir the Great, r. 980-1015) and Prince Yaroslav (the Wise; r. 1019-1054). Both rulers continued the steady expansion of Kievan Rus′ that had begun under Oleg.
Vladimir rose to power in Kiev after the death of his father Sviatoslav I in 972 and after defeating his half-brother Yaropolk in 980. As Prince of Kiev, Vladimir's most notable achievement was the Christianization of Kievan Rus′, a process that began in 988. The annals of Rus¹ state that when Vladimir had decided to accept a new faith instead of the traditional idol-worship (paganism) of the Slavs, he sent out some of his most valued advisors and warriors as emissaries to different parts of Europe. After visiting the Roman Catholics, the Jews and the Muslims, they finally arrived in Constantinople. There, they were so astounded by the beauty of the cathedral of Hagia Sophia and the liturgical service held there, that they made up their minds there and then about the faith they would like to follow. Upon their arrival home, they convinced Vladimir that the faith of the Greeks was the best choice of all, upon which Vladimir made a journey to Constantinople and arranged to marry with Princess Anna, the sister of the Byzantine emperor Basil II.
Vladimir's choice of Eastern Christianity may also have reflected his close personal ties with Constantinople, which dominated the Black Sea and hence trade on Kiev's most vital commercial route, the Dnieper river. Adherence to the Eastern Orthodox Church had long-range political, cultural, and religious consequences. The church had a liturgy written in Cyrillic and a corpus of translations from Greek that had been produced for the Slavic peoples. The existence of this literature facilitated the conversion to Christianity of the Eastern Slavs and introduced them to rudimentary Greek philosophy, science, and historiography without the necessity of learning Greek. In contrast, educated people in medieval Western and Central Europe learned Latin. Enjoying independence from the Roman authority and free from tenets of Latin learning, the East Slavs developed their own literature and fine arts, quite distinct from those of other Orthodox countries. See Old East Slavic language and Architecture of Kievan Rus for details.
Yaroslav, known as "The Wise", also struggled for power with his brothers. Although he first established his rule over Kiev in 1019, he did not have uncontested rule of all of Kievan Rus until 1036. Like Vladimir, Yaroslav was eager to improve relations with the rest of Europe, especially the Byzantine Empire. Yaroslav's granddaughter, Eupraxia the daughter of his son Vsevolod I, Prince of Kiev, was married to Henry III, Holy Roman Emperor. Yaroslav also arranged marriages for his sister and three daughters to the kings of Poland, France, Hungary, and Norway. Yaroslav promulgated the first East Slavic law code, Russkaya Pravda (Justice of Rus′); built Saint Sophia Cathedral in Kiev and Saint Sophia Cathedral in Novgorod; patronized local clergy and monasticism; and is said to have founded a school system. Yaroslav's sons developed the great Kiev Pechersk Lavra (monastery), which functioned in Kievan Rus′ as an ecclesiastical academy.
In the centuries that followed the state's foundation, Rurik's descendants shared power over Kievan Rus′. Princely succession moved from elder to younger brother and from uncle to nephew, as well as from father to son. Junior members of the dynasty usually began their official careers as rulers of a minor district, progressed to more lucrative principalities, and then competed for the coveted throne of Kiev. In the 11th century and the 12th century, the princes and their retinues, which were a mixture of Slavic and Scandinavian elites, dominated the society of Kievan Rus′. Leading soldiers and officials received income and land from the princes in return for their political and military services. Kievan society lacked the class institutions and autonomous towns that were typical of West European feudalism. Nevertheless, urban merchants, artisans, and laborers sometimes exercised political influence through a city assembly, the veche (council), which included all the adult males in the population. In some cases, the veche either made agreements with their rulers or expelled them and invited others to take their place. At the bottom of society was a small stratum of slaves. More important was a class of tribute-paying peasants, who owed labor duty to the princes. The widespread personal serfdom characteristic of Western Europe did not exist in Kievan Rus′.
Kievan Rus′ was not able to maintain its position as a powerful and prosperous state, in part because of the amalgamation of disparate lands under the control of a ruling clan. As the members of that clan became more numerous, they identified themselves with regional interests rather than with the larger patrimony. Thus, the princes fought among themselves, frequently forming alliances with outside groups such as the Polovtsians, Poles, and Hungarians. During the years from 1054 to 1224 no fewer than 64 principalities had a more or less ephemeral existence, 293 princes put forward succession claims, and their disputes led to 83 civil wars.
The Crusades brought a shift in European trade routes that accelerated the decline of Kievan Rus′. In 1204 the forces of the Fourth Crusade sacked Constantinople, making the Dnieper trade route marginal. As it declined, Kievan Rus′ splintered into many principalities and several large regional centers: Novgorod, Vladimir-Suzdal, Halych(Galich), Polotsk, Smolensk, Chernigov (modern Chernihiv), and Pereyaslav. The inhabitants of those regional centers then evolved into three nationalities: Ukrainians in the southeast and southwest, Belarusians in the northwest, and Russians in the north and northeast.
In the north, the Republic of Novgorod prospered as part of Kievan Rus' because it controlled trade routes from the Volga River to the Baltic Sea. As Kievan Rus' declined, Novgorod became more independent. A local oligarchy ruled Novgorod; major government decisions were made by a town assembly, which also elected a prince as the city's military leader. In the 12th century, Novgorod acquired its own archbishop, a sign of increased importance and political independence. In its political structure and mercantile activities, Novgorod resembled the north European towns of the Hanseatic League, the prosperous alliance that dominated the commercial activity of the Baltic region between the 13th century and the 17th century, more than the other principalities of Kievan Rus'.
In the northeast, Slavs colonized the territory that eventually became Muscovy by subjugating and merging with the Finno-Ugric tribes already occupying the area. The city of Rostov was the oldest center of the northeast, but it was supplanted first by Suzdal′ and then by the city of Vladimir, which become the capital of Vladimir-Suzdal′. There was recorded a large wave of migrations from Kiev region northward, to escape continuing excursions of the Turkic nomads from the "Wild Steppe". As the southern lands were being depopulated and more boyars, nobles, artisans arrived to the court at Vladimir, the combined principality of Vladimir-Suzdal′ asserted itself as a major power in Kievan Rus′. In 1169 Prince Andrey Bogolyubskiy of Vladimir-Suzdal′ dealt a severe blow to the waning power of Kievan Rus′ when his armies sacked the city of Kiev. Prince Andrey then installed his younger brother, who ruled briefly in Kiev while Andrey continued to rule his realm from Suzdal′. Thus, political power began to drift away from Kiev in the second half of the 12th century. In 1299, in the wake of the Mongol invasion, the metropolitan moved from Kiev to the city of Vladimir, and Vladimir-Suzdal′ replaced Kiev as a religious center for the northern regions.
To the southwest, the principality of Galich had developed trade relations with its Polish, Hungarian, and Lithuanian neighbors and emerged as the local successor to Kievan Rus′. In the early 13th century, Prince Roman Mstislavich united the two previously separate principalities, conquered Kiev, and assumed the title of grand duke of Kievan Rus′. His son, Prince Daniil (r. 1238-1264) was the first ruler of Kievan Rus′ to accept a crown from the Roman papacy, apparently doing so without breaking with Constantinople. Early in the 14th century, the patriarch of the Eastern Orthodox Church in Constantinople granted the rulers of Galicia-Volhynia a metropolitan to compensate for the move of the Kievan metropolitan to Vladimir. Lithuanian rulers also requested and received a metropolitan for Novagrudok shortly afterwards. Early in the 15th century, these Metropolia were ruled again from Kiev by the "Metropolitan of Kiev, Galich and all Rus′".
However, a long and unsuccessful struggle against the Mongols combined with internal opposition to the prince, and foreign intervention weakened Galicia-Volhynia. With the end of the Mstislavich branch of the Rurikids in the mid-14th century, Galicia-Volhynia ceased to exist; Poland conquered Galich; Lithuania took Volhynia, including Kiev, conquered by Gediminas in 1321 ending the rule of Rurikids in the city. Lithuanian rulers then assumed the title over Ruthenia.
As mentioned earlier the rise of the regional centers played a great role. Also unconventional power succession system where the power was transferred form father to son (not always the eldest, usually the favorite one) to brother to son, bred constant hatered and rivalry within the royal family. Brutal killing of siblings and relatives was a very common (more common than in Western Europe) way to obtain power.
Decline of Constantinople - a main trading partner of Kiev Rus, played a tremendous role in the decline. The trade route From Varangians to Greeks, along which the goods were moving from the Black Sea (mainly Byzantine) through Eastern Europe to the Baltic, was a cornerstone of Kiev wealth and prosperity. Kiev was the main power and initiator in this relationship, once the Byzantine Empire fell into turmoil and the supplies became erratic, profits dried out, and Kiev lost its appeal. Other routes that went through Kiev were not remotely as significant. The other major Volga Trade Route laid far to the east and north of Kiev and later contributed to the rise of Muskovia. Moving of the Orthodox Metropolitan See from Kiev to Vladimir significantly undermined Kiev authority. The Mongol Invasion finished off all hopes for reintegration.
The economic development of Kievan Rus may be translated into demographic statistics. Around 1200, Kiev had a population of 50,000 people, Novgorod and Chernigov both had around 30,000 people. By comparison, in Anglo-Norman England, where urbanization was as advanced as anywhere in Europe north of the Mediterranean, London had around 12,000 inhabitants, and England's second city, Winchester, about 5,000. Constantinople had population of about 400,000 people around 1180. The Soviet scholar Mikhail Tikhomirov calculated that Kievan Rus' on the eve of the Mongol invasion had around 300 urban centers.
Kievan Rus' also played an important genealogical role in European politics. Yaroslav the Wise, whose stepmother belonged to the greatest dynasty to rule Byzantium, married the only legitimate daughter of the king who Christianized Sweden. His daughters became Queens of Hungary, France, and Norway, his sons married the daughters of a Polish king and a Byzantine emperor (not to mention a niece of the Pope), while his granddaughters were a German Empress and (according to one theory) the Queen of Scotland. A grandson married the only daughter of the last Anglo-Saxon king of England. Thus the Rurikids were the most well-connected royal family of the time.
Unsurprisingly, Kievan Rus' left a powerful legacy. The leader of the Riurikid Dynasty united a large territory inhabited by East Slavs into an important, albeit unstable, state. After Vladimir accepted Eastern Orthodoxy, Kievan Rus' came together under a church structure and developed a Byzantine-Slavic synthesis in culture, statecraft, and the arts.
In the Western periphery, the Kievan Rus' legacy was carried for two more centuries by the Principality of Galicia-Volhynia. Later, as these lands along with the territories of modern central Ukraine and Belarus fell to the Gediminids, the powerful, largely Ruthenized Grand Duchy of Lithuania, drew heavily on Rus' cultural and legal traditions. On the northeastern periphery of Kievan Rus', those traditions were adapted to form the legacy that gradually gravitated towards the Moscow rulers, eventually leading to modern Russian statehood. Thus, modern Russia can trace a lineage to historic Rus' via Vladimir-Suzdal, Muscovy, and the Russian Empire. In the very north, the Novgorod and Pskov Feudal Republics carried on a separate and less autocratic version of Rus' legacy into the 16th century until they were absorbed by Muscovite Russia.