Yaroslav The Wise

Yaroslav I, Grand Prince of Rus', known as Yaroslav the Wise (Old Norse: Jarizleifr; Old East Slavic and Russian Ярослав Мудрый; Ukrainian: Ярослав Мудрий; c. 978 – 20 February 1054) was thrice Grand Prince of Novgorod and Kiev, uniting the two principalities for a time under his rule. Yaroslav's Christian name was George (Yuri) after Saint George (Old Russian: Гюрьгi, Ghyurghi).

A son of the Varangian (Viking) Grand Prince Vladimir the Great, he was vice-regent of Novgorod at the time of his father’s death in 1015. Subsequently, his eldest surviving brother, Svyatopolk the Accursed, killed three of his other brothers and seized power in Kiev. Yaroslav, with the active support of the Novgorodians and the help of Varangian mercenaries, defeated Svyatopolk and became the Grand Prince of Kiev in 1019. Under Yaroslav the codification of legal customs and princely enactments was begun, and this work served as the basis for a law code called the Russkaya Pravda ("Rus Truth "). During his lengthy reign, Rus' reached the zenith of its cultural flowering and military power.