He said she was far brighter than most British girls he knew (she was also a very talented musician), and soon Queen Victoria was to be impressed by the intelligence of the girl, whom she called "Sally".

She remained Sally's friend and protector until she was old enough to marry. Sally lived with the Forbes family for a year, then was sent to Sierra Leone for her education (the Queen thinking the damp weather would be bad for her health).

But Sally was very unhappy, and in 1855 the Queen agreed for her to return to England. She lived a comfortable life with patrons in Gillingham, and then Brighton.

In August 1862 Sally reluctantly submitted to marriage with James Davis, a Yoruba businessman. It seems that Sally put up resistance, but having deemed him suitable the Queen put pressure on her to accede to his request.

The wedding, in Brighton, was extravagant: there were sixteen bridesmaids and the wedding party was made up of white ladies with African gentlemen, and African ladies with white gentlemen. In the above picture you can see her in her wedding dress.

She visited the Queen in 1867 with her daughter – whom she christened Victoria and also became the Queen's godddaughter – and then returned to Lagos where she had two more children.

Sadly, she'd been in poor health for some time: she had tuberculosis, and died at the age of 37 in 1880. She was buried in Funchal Madeira.

Upon her death the Queen wrote in her diary: "Saw poor Victoria Davies, my black godchild, who learnt this morning of the death of her dear mother". Queen Victoria was so proud of Sally's daughter that when she passed her music examination, teachers and children had a day's holiday.

Sarah's story shouldn't be romanticized too much (she had a comfortable but somewhat unhappy life), but it's certainly surprising.