The revival of the Kingdom of Georgia was set back after Tbilisi was captured and destroyed by the Khwarezmian leader Jalal ad-Din in 1226. The Mongols were expelled by George V of Georgia (r. 1299–1302), son of Demetrius II of Georgia (r. 1270–1289), who was named "Brilliant" for his role in restoring the country's previous strength and Christian culture. George V was the last great king of the unified Georgian state. After his death, local rulers fought for their independence from central Georgian rule, until the total disintegration of the Kingdom in the 15th century. Georgia was further weakened by several disastrous invasions by Tamerlane. Invasions continued, giving the kingdom no time for restoration, with both Black and White sheep Turkomans constantly raiding its southern provinces.