Mistislaw, also known as Mstislav (d. after 1018), was an Elbe Slavic prince of the Nakonid lineage and ruled over the Obotrites in what is now Mecklenburg and eastern Holstein from 990/995 to 1018.
The Nakonids were among the most powerful Christian Slavic princes in the second half of the 10th century. In the retinue of the Saxon Duke Bernhard I, Mistislaw participated in Otto II's campaign against the Saracens in southern Italy in 982, from which he returned with only a few survivors. In the subsequent Slavic revolt of 983, the Nakonids relinquished their sovereignty over several Obotrite branches to the victorious Lutici. Upon the death of his father, Mstivoj, in 990 or 995, Mistislaw attempted to establish royal rule over the remaining peoples. While he managed to secure the support of the Church and the Empire, the opposition within the Obotrites joined forces with the Lutici. From 1003 onwards, Mistislaw's ability to secure Saxon support was eroded by Henry II's alliance with the Lutici against the Polish prince Boleslaw I. This ultimately resulted in Mistislaw's inability to assert his authority. In February 1018, the Lutici invaded the Obotrite kingdom, incited unrest among the population, and compelled Mistislaw to seek refuge in the Saxon Bardengau.
The majority of recent research views Mistislaw as a Christian Slavic prince with close ties to the Holy Roman Empire. This research suggests that his attempt to reorganise the Obotrite kingdom from a personal state to a territorial state failed, despite the support of the Church and the Saxon duchy.