Demne

Demna, a shortened form of Demetrius, was the prince whose exclusion from the Georgian throne and terrible punishment secured the crown for the line of George III and, through him, Queen Tamar. He was the son of David V, the eldest son of Demetrius I, who had deposed his father in 1154 only to die after six months on the throne in 1155. By precedent Demna, an infant born about 1155, should have succeeded; instead the old king Demetrius was restored and crowned his younger son George as co-ruler, and George III took the throne alone on his father's death in 1156. The Armenian historian Vardan Areveltsi alleged that David V had been poisoned by the nobles Sumbat and Ivane Orbeli in concert with George.

Demna grew up in the care of Ivane Orbeli, the amirspasalar or commander-in-chief of the kingdom. Stepanos Orbelian, writing his family's history in 1297, maintained that George had sworn to rule only until his nephew came of age and then broke his oath. In 1177 the Orbelis and a wide coalition of nobles rose in Demna's name, crowned him at the castle of Agara, and marched on Tbilisi with a force the chronicle puts at thirty thousand. The surprise failed. George III, relying on Kipchak mercenaries and mountaineers, split the rebels by force and by promises, and Ivane withdrew to the fortress of Lori, which the royal army besieged while overrunning the rebel lords' estates. Help sought from the Eldiguzid atabeg in Tabriz arrived too late.

Demna was the first to surrender, throwing himself on his uncle's mercy. He was blinded and castrated to end his line's claim, and died in captivity, most modern accounts say in 1178 or 1179, probably of his injuries. Ivane Orbeli was executed and his family all but destroyed, its survivors taking refuge in Armenia. With Demna gone, the crown passed to George's daughter Tamar, and the Georgian golden age descended through her line rather than his.