When did Kim Jong-un become supreme leader of North Korea?
North Korea's leader Kim Jong-un assumed power after his father, Kim Jong-il, passed away in 2011 following a long stint as supreme leader since 1994. Kim Jong-un is the third in a familial succession of leaders, with his grandfather, Kim Il-sung, holding highest office in North Korea since the country was established until his death. Known for his willingness to display the country's destructive power via nuclear bomb tests, Kim Jong-un has reportedly continued human rights violations started under his father and executed or removed all who could challenge his rule. Source: Biography.com