The architecture of Kievan Rus' comes from the medieval state of Kievan Rus' which incorporated parts of what is now modern Ukraine, Russia, and Belarus, and was centered on Kiev and Novgorod. Its architecture is the earliest period of Russian and Ukrainian architecture, using the foundations of Byzantine culture but with great use of innovations and architectural features. Most remains are Russian Orthodox churches or parts of the gates and fortifications of cities.
After the disintegration of Kievan Rus' followed by Mongol invasion in the first half of the 13th century, the architectural tradition continued in the principalities of Novgorod, Vladimir-Suzdal, Galicia-Volhynia and eventually had direct influence on the Russian, Ukrainian, and Belarusian architecture. The Old Russian architecture of churches originates from the pre-Christian Slavic zodchestvo (Russian: зодчество - construction).