He was a younger brother and adopted son of Emperor Tự Đức. After his nephew (and adoptive half-brother) Dục Đức was deposed by court officials following a three-day reign in 1883 he reasserted the family's claim on the throne. However he presided over his nation's defeat by the French navy at the Battle of Thuận An in August 1883, and on 25 August 1883 he signed a treaty which made Vietnam a protectorate of France, ending Vietnam's independence. For this, he was deposed and forced by officials to commit suicide.
^Bruce M. Lockhart, William J. Duiker Historical Dictionary of Vietnam 2010 -Page 154 "A younger brother and adopted son of Emperor Tự Đức, he succeeded his nephew Dục Đức after the latter was deposed by court officials in 1883. Hiệp Hòa attempted to wrest power back from these officials, but he was not strong enough and he, in turn, was deposed and forced to commit suicide after a ..."