Slavomir (Latin: Sclagamarus, Czech and Slovak: Slavomír) was a duke of Moravia (871). He led a revolt against the Franks who had annexed Moravia during the incarceration of his relative, Svatopluk I.
The previous ruler, Rastislav, was arrested and handed over to the Franks by his own nephew, Svatopluk I in 869 or 870. However, Svatopluk himself was arrested in 870 on the order of the Louis the German's son, Carloman who appointed two Frankish lords, William and Engilschalk to rule over Moravia. Believing that Svatopluk was dead, the Moravians selected Slavomir to be their ruler. Since Slavomir had already been a priest, his election likely indicates that the Moravian ruling dynasty has run out of male heirs by that time.
With Slavomir in rebellion, Carloman decided to employ the common strategy of using one "barbarian" leader to wage war against another. For this purpose he released Svatopluk from prison, and sent him back to Moravia with a large Bavarian army to depose Slavomir. Once again in the battlefield, however, Svatopluk bolted from the Frankish ranks, joined forces with Slavomir, and defeated the army he had just left. Therefore, Svatopluk became again the undisputed ruler of Moravia.