Because people from all around the world came to live in Victorian Britain, not just black people.
Years ago, I visited Thetford, mostly for the fine motte and to see the places that had been the scenes of outdoor location shooting for Dad's Army - despite being nowhere near the sea, Thetford was actually Walmington-on-Sea!
And near the river, we came upon a statue of a Sikh Prince.
Prince Duleep Singh lived near to Thetford, at Elvedon Estate (now owned by the Guinness family). Before that he had lived in Yorkshire and Scotland, where he was known as the Black Prince of Perthshire. Although he lived the life of an aristocrat, and became the fourth best shot in England (apparently) in game shooting circles, he was not living in England by choice.
At the age of five, he was declared Maharajah of the Sikh Empire, after four of his predecessors were assassinated. After the First Anglo-Sikh War, he and his mother were imprisoned by the British, and at the age of fifteen he was sent to England. Queen Victoria befriended him, but he was separated from his mother for thirteen years, when she was allowed to come to England to be with him for the last two years of her life. He visited India only twice - once to be re-united with his mother, Maharani Jind Kaur, and once to scatter her ashes. He attempted to return to India in 1886, but only got as far as Aden, where he was arrested and sent back to Britain.
He died in Paris, at the age of 55, and is buried in Elvedon Church, beside his wife Bamba and his son Edward Albert Duleep Singh. In his youth, he converted to Christianity, but later (while at Aden on his way back to India) re-converted to Sikhism.
Prince Duleep Singh married twice - he and Bamba Muller had six children, and his second wife Ada Douglas Wetherill had two children. None of the eight children had legitimate children of their own, ending the line of the Sikh royal family. Princes Victor and Frederick went to Eton in the 1870s.
He met Bamba, the daughter of a German banker and a Coptic slave, in Egypt on his way back from scattering his mother's ashes, and they were married in Alexandria.
Ada was supposed to be a French princess, but was actually the Prince's mistress, who went to join him in Paris when he abandoned his first family. This was after his failed attempt to return to India. Ada was with him when he travelled to St Petersburg to try to persuade the Czar to invade India from the north and re-install him as ruler.
One of the most interesting of his children was Princess Sophia Duleep Singh, who became a suffragette. She lived in a "grace and favour" house at Hampton Court, and visited India in 1907. When she came back, she turned her attention to women's suffrage as an associate of Mrs Pankhurst, and the aid of the Indian soldiers during the First World War. She worked as a nurse among the Indian wounded soldiers in Brighton.
She died in 1948, and her ashes were scattered in India.