One of his three brothers was Alexander von Bach (1813-1893), effectively president of Austro-Hungary from 1849 to 1859. Under him "The Austrian Empire became, for the first and last time, a fully unitary state." (A.J.P.Taylor).
Molbe's brother Eduard (1814-1884) was successively governor of several provinces of Austro-Hungary, including ��sterreich ob der Enns or Lower Austria (1852-1867).
Another brother was the composer Otto Bach (1833—1893).
One of his grandsons was the historian Heinrich Demelius (1893-1987).
