Married Julia Goldsmid, daughter of a wealthy bullion broker.

Father of Laura de Stern and three other children. His son, Herbert, became Lord Michelham.

Hermann and his brother David settled in London in 1844, founding the finance company, Stern Brothers. The firm soon became one of the most successful and reputable banking-houses in the City of London .

In recognition of their work connected with Portuguese finance, the King of Portugal created Hermann a Baron and David a Viscount.

When Hermann died in 1887, he left £3.5 million – one of the wealthiest estates of Victorian Britain.