Kim Jong-un took on the mantle of North Korea's supreme leadership with little political or military experience behind him. Kim Jong-il, North Korea's "Dear Leader", was in the process of grooming Kim Jong-un as his successor when he died on 17 December 2011. Immediately after his father's death, the younger Kim was hailed as "the great successor". He was named head of the party, state and army within a fortnight of his father's death. In January 2016, Mr Kim shot to global headlines again when he oversaw what the regime claimed was an underground hydrogen bomb test -
its second nuclear test since he came to power. Previously, his most high-profile act had been to purge and execute his uncle, Chang Song-thaek, who state media said had been plotting a coup, in December 2013.