This is Sarah Forbes Bonetta. Her daughter Victoria became the god-daughter of Queen Victoria of England. She was popularly known as the "African Princess". This portrait was taken by the French photographer Camille Silvy (1834-1910) at his London studio in 1862, a month after her marriage to James Labulo Davies, a West African merchant.
As a young girl.
With her husband in 1862. She was around 20.