Mstislav I Vladimirovich the Great (Russian: ???????? ???????????? ???????,(June 1, 1076 – April 14, 1132) was the Grand Prince of Kiev (1125–1132), 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.