Rajadhiraja Chola II (1166–1178 CE) reigned as the Chola king succeeding Rajaraja Chola II. According to historian N. Sethuraman, Rajadhiraja was not the direct descendant of Rajaraja Chola II but was a son of his sister. Rajaraja Chola II chose Rajadhiraja as his heir in 1166 as he did not have any sons of his own.
Soon after the installation of Rajadhiraja II, a fierce succession dispute in the Pandya country led to the intervention of the Chola and the Sinhalese rulers on opposite sides which brought misery to both. Out of the ashes of this civil war arose the Pandya power which in its renewed strength soon swallowed both the Chola and Sinhalese kingdoms.
Read more about Rajadhiraja Chola II: Pandya Civil War, Empire Weakens, Death and Succession