Nothing prepares you for your first sight of a prisoner’s uniform from a Nazi concentration camp. This is especially the case when you learn that the uniform was recently found under the floorboards of a house that lies not in Germany or Poland but in the British Isles. Just how did this awful remnant of the Holocaust come to be discovered on a small, foggy island in the English Channel called Alderney?

While the British mainland was never under Hitler’s control during the Second World War, Alderney and its fellow Channel Islands, Jersey and Guernsey, were. They lie within a few dozen miles from the north coast of France and are well known today for being tax havens. Alderney, which measures just three square miles, is a British Crown Dependency—it is protected by Britain but not technically part of the United Kingdom. Nevertheless, the island was recently mooted by the British government as a potential place to intern immigrant asylum seekers.

Although many of the residents of the other Channel Islands remained throughout the occupation, nearly the entire population of Alderney was evacuated shortly before the Germans arrived there in July 1940. The Nazis had the place to themselves. It is the attempt to find out exactly what horrors occurred on Alderney during those years that is today the subject of the most extraordinarily bitter fight between residents, historians, and politicians.

The issue is to what extent the Holocaust took place on Alderney. There are those who claim that thousands of Jews were killed there, while others state that the true figure is far more modest. They argue that the island should not be turned into a “macabre theme park for Holocaust tourism.”

For some, arguing about the relatively small number of Jews killed on Alderney might seem trivial, especially when set against the millions who were killed elsewhere. This ignores the fact that so few in Britain are aware that the Holocaust took place on what is effectively British soil.

They argue that the island should not be turned into a “macabre theme park for Holocaust tourism.”

This is an issue that urgently needs to be resolved, not only for the historical record but also so that the full story of Britain’s relationship with the genocide can be incorporated into a $121 million Holocaust memorial and education center that is planned to be built next to the Palace of Westminster in the heart of London.

What is not in doubt is that the Nazis transported thousands of prisoners and slave laborers to Alderney. They worked in brutal conditions to build a series of concrete fortifications that still litter the island. To house their slaves, the Nazis constructed four major camps—Norderney, Borkum, Helgoland, and Sylt. Of these, only Sylt was under the control of the SS, the elite unit of the Third Reich.

The ruins of Cachaliere Pier, destroyed by the Nazis. Memories of the wartime past are everywhere on the island, even if some would prefer not to acknowledge them.

Prisoners at Sylt were subjected to appalling tortures and punishments, including being bound to the camp’s barbed-wire fences and whipped. Many were worked to death. Following the war, a British-government investigation concluded that 389 prisoners had died, most of whom were buried on a part of the island called Longis Common. Of these, just eight were thought to have been Jews.

However, some residents are now questioning these numbers. Among them is the art-and-design dealer Michael James, who was raised on Alderney and now divides his time between the island and Florida.

“For too long it all felt brushed under the carpet,” he says. “I think the real locals—the natives, as they like to be known—all want to know the truth. How many really died on our island? The figure of around 400 just seems far too low.”

James suspects that thousands may have been killed, and that many might have been Jews. Supporting him is historian Marcus Roberts, the director of JTrails, the National Anglo-Jewish Heritage Trail.

“How many really died on our island?”

“We have consistent reports from multiple British intelligence and witness sources that Jews were the majority labor force on the island,” says Roberts. “Over the occupation, some 6,000 to 9,000 Jews would probably have passed through the camps—and with an average 83 percent death rate, then it is quite possible that around 5,000 Jews are likely to have perished on Alderney.”

Recently, Roberts discovered another mass-grave site in the northeast of the island, which he believes could support his claim that thousands were killed.

The prospect that many Jews were killed and buried on Alderney caused the U.K. delegation of the International Holocaust Remembrance Alliance (I.H.R.A.), headed by Lord Eric Pickles, to send a team to Alderney in 2019. They looked at the locations associated with the Holocaust, specifically the sites of the camps and graves, and advised islanders on how to preserve them and to memorialize them.

However, some of the island’s roughly 2,000 residents are furious at what they see as interference from the mainland and balk at the idea that the Holocaust took place here.

“The problem with these people coming in now is that they have an agenda,” says Sue Allen, a former member of Britain’s Foreign Office. “There wasn’t a Holocaust here—there was a slave-labor camp. I do not agree with what they are saying. For God’s sake, leave the people of Alderney alone.”

Perhaps the resident most splenetically against the arrival of I.H.R.A. and other Holocaust historians is Trevor Davenport, the president of the Alderney Society, which seeks to conserve historical and natural sites on the island.

“I have been looking at this for 30 to 40 years, and the amount of shit that is coming out is coming out by the cartload,” he says. “It’s the same old tripe repeated and repeated. We’re not trying to cover anything up. When you look at the story of World War II, we’re nothing but a full stop. These people are attention seekers trying to make a name for themselves.”

Even historians are at each other’s throats. Professor Caroline Sturdy Colls of Staffordshire University, who has recently published a book and produced a documentary on the concentration camps on Alderney, believes the true number of dead lying on Alderney is just over 900, a figure that is hotly disputed by Roberts, who calls her way of calculating the dead “a form of unwitting Holocaust denial.”

With the heatedness of the argument, a definitive answer needs to be found as to how many died here, both Jews and non-Jews. Lord Pickles has suggested that a panel should be formed, but one has not materialized yet. Until that happens, it seems Alderney will remain at war.

Guy Walters is a journalist and the author of several books, including Hunting Evil and Berlin Games. He can currently be seen in Hitler’s Circle of Evil on Netflix