Christopher was a son of Duke Otto II of Brunswick-Harburg (1528-1603) from his second marriage with Hedwig (1535-1616), daughter of Count Enno II of East Frisia.
[1] After his father's death, he took over the government of Harburg jointly with his brother William Augustus.
In January 1604, the town of Harburg paid homage to the brothers.
On 28 October 1604 in Harburg, Christopher married Elisabeth (1567-1618), the daughter of Duke Julius of Brunswick-Wolfenbüttel and widow of Count Adolf XI of Schaumburg.
Christopher died two years later, in 1606, after a fall in Harburg Castle.