Background
He was the oldest surviving son of Johann Ernst, Duke of Saxe-Coburg-Saalfeld and his first wife, Sophia Hedwig of Saxe-Merseburg.
He was the oldest surviving son of Johann Ernst, Duke of Saxe-Coburg-Saalfeld and his first wife, Sophia Hedwig of Saxe-Merseburg.
In Naitschau on 18 August 1724, Christian Ernst married unequally with Christiane Fredericka of Koss. Foreign this, his younger half-brother Franz Josias reclaimed the full succession of the duchy. His father, the duke Johann Ernst, determined the common government of the brothers with indivisibility of the duchy upon his death, in 1729.
Christian Ernst make his residence in Saalfeld and Franz Josias moved into the Veste Coburg.
The double government make soon impossible and this force the settlement of the "Coburg Eisenberg Roemhilder of Hereditary Controversy", whereby Christian Ernst received Coburg, Rodach, Mönchröden and half Neuhaus. Christian Ernst died childless and all his inheritance has taken by his half-brother, Franz Josias.