For more than a year, it has been the millstone around Prince Harry's neck, a gold‑plated slice of taxpayers' largesse that reeked of privilege and entitlement.
But to Harry and Meghan, the £2.4 million ($4.7 million) of public money that was lavished on renovating Frogmore Cottage, only for it to be shuttered and abandoned along with the rest of their royal lives, represented something far more intrinsic.
He saw it as a chain that shackled them to the land of his birth, inhibiting their efforts to be truly free of the royal family and, crucially, of their media critics.
In his eyes, the money was not a loan from a generous nation pleased to be helping this young royal couple find its feet after their joyful wedding, but rather a stick with which to beat them.
So paying back every penny to the public purse, having previously offered to do so at the rate of £18,000 ($35,000) a month (a deal of such indulgence it would have taken them 11 years to repay the debt), is highly significant.
In the short term, it is designed to silence the drumbeat of criticism to which they perceive they are subject. But will it really end what they complain of as unjustified "public interest" in their new lives?
Surely by embarking on such a high-profile life in the entertainment capital of the world, where every resource is choreographed for maximum publicity, such a move raises more questions than it answers?
It can be no coincidence that this remarkable gesture comes just days after it was revealed that the couple had signed a production deal with Netflix, estimated to be worth £75 million ($147m).
Many will wonder if this payment to the Sovereign Grant was part of the first instalment of that extraordinary deal. But while royal officials were digesting the implications, another equally bold announcement was being released by the Duke and Duchess.
A source close to the couple confirmed that they were no longer receiving financial support from Harry's father, the Prince of Wales, either from the Duchy of Cornwall or his private income.
This, too, marks a fork in the road for Harry and Meghan, although insiders suggest they may already have received the full amount of the stipend they expected from Charles for this year anyway.
What it does do, however, is signal that their divorce from Britain is permanent, while removing any pretence that they might still have a future role in the Royal Family.
Harry could, of course, have avoided this whole sorry saga before it ever became an issue. With an estimated fortune of £20 million ($39m) inherited from his mother's estate and trust funds from the Queen Mother, he could have afforded to pay for the renovation himself.
What he failed to understand then, and probably still doesn't now, is not that there was public resentment at the cost of refurbishing Frogmore, but that the public felt cheated when Harry chose to keep secret details about son Archie's birth and christening.
"It sent the message that they were happy to take public money for granted, but not if it meant having to share things with the public they didn't want to," says a courtier.
"Ever since, it has become more and more toxic."
For now, questions remain about how the money has been repaid and who knew about it. Royal aides suggested that, although the timing had come as a surprise, it was not entirely unexpected.
Harry has been determined to emphasise his and Meghan's lack of reliance on British taxpayer funds, by first meeting the cost of their substantial security bill and now by paying back the Sovereign Grant. They believe it will remove what they consider to be media intrusion into their lives.
But criticism of the lavish renovations of Frogmore Cottage have hardly been confined to the media. At the weekend, Sir Geoffrey Clifton-Brown, deputy chairman of Parliament's public accounts committee, noted: "Clearly anyone who has borrowed taxpayers' cash needs to pay it back as quickly as possible; £2.4 million is a lot and, even if you paid back £250,000 a year, it would still take a decade."
Harry may see his new-found wealth, which has allowed him to pay back this money, as gaining liberty and escaping his critics. But it may have unforeseen consequences.
While his father contributed to Harry and Meghan's life, there was still a link, however tenuous, anchoring him to his country and his family. Without it, Harry may find himself more adrift than ever.