Prince Harry's admission fuels debate over royals' link to slavery

London — The publisher of Prince Harry's new memoir Spare says it's selling at a record-setting pace. Readers bought more than 1.4 million copies of the Duke of Sussex's book the day it was published last week, and it's still making headlines.

One thing Harry put down on paper that has continued to stoke debate was a brief comment that his family had made a fortune from the trans-Atlantic slave trade.

Britain's centuries-old monarchy is known for many things, from pomp and pageantry to family discord. Its historical connection to slavery, however, has been far less a part of the public discussion, at least until recently.

"I mean it goes all the way back to Elizabeth I," Esther Stanford-Xosei, a lawyer and reparations expert told CBS News. She said there was no doubt that the British monarchy was "heavily involved" in the financing of enslavement, including the voyages of slave traffickers between Africa, Europe and the Americas.

But Stanford-Xosei said the royal family were "also beneficiaries of the labor of enslaved Africans."

"The governor of the Royal African Company was James II, otherwise known as the Duke of York," she noted, referring to one of the major business enterprises involved directly in enslaving and transporting Africans in the 17th and 18th centuries.

"They also found ways of branding African people with the inscription 'DY,' for Duke of York," Stanford-Xosei said. So many slaves will literally have had the initials of a senior member of the royal family permanently and indelibly etched onto their bodies.

Contemporary members of the British royal family, including Prince William, Harry's brother and the heir to the throne, have expressed sadness about their links to the slave trade, but none has ever apologized for the direct role their ancestors played.

"The appalling atrocity of slaver forever stains our history," William said on a visit to Jamaica last year. "I want to express my profound sorrow."

"The reason why he doesn't go further is that he's aware [of] what it will mean to actually apologize, in terms of the legal obligation to make reparation," suggested Stanford-Xosei. She said William and his family feared it would cost the monarchy, "not only money, but status… He will be exposing the criminality of this institution."

Historians say it's impossible to calculate exactly how much wealth the monarchy generated from trafficking human beings, but when William and Kate visited Jamaica last year, they were met by protests demanding not just an apology, but reparations.