Mstislav I of Kiev

Mstislav I Vladimirovich Monomakh (Old East Slavic: Мьстиславъ Володимѣровичъ Мономахъ, romanized: Mĭstislavŭ Volodiměrovičŭ Monomakhŭ; Christian name: Theodore (Fedor); February 1076 – 14 April 1132), also known as Mstislav the Great, was Grand Prince of Kiev from 1125 until his death in 1132. After his death, the state began to quickly disintegrate into rival principalities.

He was the eldest son of Vladimir II Monomakh by Gytha of Wessex. He is figured prominently in the Norse Sagas under the name Harald, to allude to his grandfather, Harold II of England.