Ernst II von Gleichen-Harburg

Ernst II of Gleichen-Harburg (c. 1152 – 1170) was a son of Count Ernst I of Tonna. From 1152 he ruled with his brother Erwin II as count of Gleichenstein, holding Harburg Castle in the Eichsfeld and the advocacy of Gerode Abbey. In 1162 he founded the Cistercian Reifenstein Abbey at Kleinbartloff.

His castles of Harburg and Rusteberg were destroyed in 1165 during wars between the archbishops of Mainz and the Thuringian landgraves, who captured him and had him beheaded in 1170.