Christian Günther I and his brothers were still minors when their father died in 1586 and they inherited Schwarzburg-Sondershausen.
Their uncles Counts Anthony I (1505–1573) and John VII (1540–1603) of Oldenburg took up the regency.
Schwarzburg-Sondershausen suffered badly during the Thirty Years' War, especially the city of Arnstadt and its surroundings.
The brothers added the north wing to Sondershausen Palace.
On 15 November 1612, Christian Günther I married Anna Sibylle (1584–1623), the daughter of Count Albert VII of Schwarzburg-Rudolstadt.