Kim Jong Un's Rise to Power
September 2010: Promoted to four-star general by his father, Kim Jong Il
December 2011: Kim Jong Il dies of a heart attack, leaving power to relatively inexperienced Kim Jong Un
February 2012: North Korea makes nuclear concessions in exchange for badly needed food aid from U.S.
April 2012: North Korea tries unsucessfully to launch rocket, leading U.S. to cancel food aid deal
May 2012: Pyongyang vows to continue developing its nuclear program, amid concerns it could conduct a third nuclear test
July 2012: Army chief Ri Yong Ho unexpectedly removed from his post because of undisclosed "illness," replaced by obscure general
July 2012: Formally declared head of North Korea's 1.2 million-strong military, effectively completing his succession to power