988 CE
The Christianization of Kievan Rus under Grand Prince Vladimir I aligned the largest Slavic state with the Eastern Orthodox Church and Byzantine civilization, a decision with profound consequences for Russian and Eastern European history.
Religion & Governance
- Grand Prince Vladimir I of Kiev accepted Eastern Orthodox Christianity and was baptized, traditionally said to have occurred at Chersonesus in Crimea, following negotiations with the Byzantine Empire that included his marriage to Anna, sister of Byzantine Emperor Basil II.
- Vladimir ordered the mass baptism of the inhabitants of Kiev in the Dnieper River and the destruction of pagan idols, beginning the conversion of Kievan Rus to Orthodox Christianity in a top-down process that would transform the culture, law, and identity of the Eastern Slavic peoples.
- The adoption of Byzantine Christianity brought with it the Cyrillic alphabet, Byzantine art and architecture, and the ecclesiastical and legal traditions of Constantinople, orienting Kievan Rus toward the Eastern Orthodox world rather than the Latin West.
Climate & Environment
- Atmospheric carbon dioxide concentration was approximately 276 parts per million, as later confirmed by ice core analysis.
Population & Demographics
- World population is estimated to have been approximately 308 million.