The Tale of Past Years (Old East Slavic: Повѣсть времѧньныхъ лѣтъ, Pověstĭ Vremęnĭnyhŭ Lětŭ) or Primary Chronicle is a history of Kievan Rus' from about 850 to 1110, originally compiled in Kiev about 1113. The work is considered to be a fundamental source in the interpretation of the history of the Eastern Slavs.
Tradition long regarded the original compilation as the work of a monk named Nestor (c. 1056 – c. 1114); hence scholars spoke of Nestor's Chronicle or of Nestor's manuscript. His compilation has not survived. Nestor's many sources included the earlier but now lost Slavonic chronicles; the Byzantine annals of John Malalas, a Greek chronicler, who in 563 produced an 18 book work of intertwined myth and truth; and the Byzantine annals of George Hamartolus, a monk, who tried to adhere strictly to truth, and whose works are the unique contemporary source for the period 813–842. Sources of Nestor's Chronicle also included byliny (singular bylina), which were traditional East Slavic oral epic narrative poems; Norse sagas; several Greek religious texts; and oral accounts of Yan Vyshatich and of other military leaders. Nestor worked at the court of Sviatopolk II of Kiev (ruled 1093–1113) and probably shared Sviatopolk's pro-Scandinavian policies.
The early part of the Chronicle features many anecdotal stories, among them those of the arrival of the three Varangian brothers, the founding of Kiev, the murder of Askold and Dir, ca. 882, the death of Oleg in 912, the "cause" of which was reported foreseen by him, and the thorough vengeance taken by Olga, the wife of Igor, on the Drevlians, who had murdered her husband. Her actions secured Kievan Rus' from the Drevlians, preventing her from having to marry a Drevlian prince, and allowing her to act as regent until her young son came of age. The account of the labors of Saints Cyril and Methodius among the Slavic peoples also makes a very interesting tale, and to Nestor we owe the story of the summary way in which Vladimir the Great (ruled 980 to 1015) suppressed the worship of Perun and other traditional gods at Kiev.