How can it have taken us so long to get around to the Mitfords? This group of aristocratic English sisters were, in their time, the very personification of useful stoogery. They were to totalitarianism what the Spice Girls were to pop music.

Well, not all of them. There were six girls in toto. Pamela (1914-48) was “the boring Mitford”; Deborah (1920-2014) was the respectable one, marrying a duke and ending up being named a Dame Commander by Queen Elizabeth II for her charitable work. Nancy (1904-73) became a famous novelist. There was also a brother, Tom (1909-45), who, after refusing to take arms against the Axis powers because he was himself a fascist, was sent by the British Army to fight in Burma, where he died in battle.

But the other three sisters were – not to put too fine a point on it– pretty horrific. And one of the things that are horrific about them is that many people who should have known better celebrated them as the epitome of fabulousness. Yes, their politics might have been offensive – but oh, how beautiful, elegant, sophisticated, witty, charming, and magnetizing they were!

Just how offensive were their politics? Just for starters, take Unity (1914-48). As some observers have joked, she was destined from conception to be a Nazi: she was conceived in an Ontario town called (of all things) Swastika and, just to top it off, was given the middle name Valkyrie. A beautiful blonde, over six feet tall, she kept a pet rat and pet snake. From an early age, she was a full-fledged Jew-hater and Nazi-lover. Her life goal was to meet Hitler, and she moved to Munich in 1934 so she could learn German and thus be able to converse with him when that magical encounter occurred.

Once in the Third Reich, Unity lost no time networking with the Nazi beau monde. After the Nazi newspaper Der Stürmer published a letter in which she proclaimed her anti-Semitism, the paper’s editor, Julius Streicher, was so impressed that he invited Unity to speak to a crowd to 200,000 at a summer festival. He also invited her to his home, where after a dinner party, by her own account, he brought up Jews “from the cellar” and made them “eat grass to entertain the guests.” She gave no sign of finding this spectacle offensive. Far from it.

While waiting to bump into the Führer, Unity also began the practice – buckle your seatbelts, now – of inviting groups of SS officers to her flat, where, beneath large swastika banners and surrounded by framed portraits of Hitler, they ravished her in sadomasochistic orgies while the “Horst Wessel Song” (the Nazi Party anthem) played on a victrola. These erotic escapades were conceived by Unity as a kind of “eucharist” – as dark, perverse acts of Hitler-worship.

Then came the day she described in a letter to her father as the “most wonderful and beautiful” of her life: she finally met Hitler. He had heard about her antics with his SS men, and was curious about (which is to say, apparently turned on by) them. She told him that “she only thought of him during these acts, and they were a symbol of her submission to his control.” He told her to keep up with the SS sex sessions, and over the next few years she socialized with the Führer frequently, routinely recounting to him the details of her latest gang-bang.

Hitler was so fond of Unity that he let her pick out a new apartment for herself from a list of those that had been expropriated by the authorities from their rightful Jewish owners. (Reportedly, “the owners of the one she chose sobbed as they watched her comment on the curtains.”) Hitler also told Unity that the two of them would spend the afterlife together, and he put it in her head that at some point she would have to kill herself so that they could be reunited in Valhalla. She was so close to him, and so fervent in her admiration, that the British Secret Services described her as being “more Nazi than the Nazis.”

It was over lunch in August 1939, only three weeks before the invasion of Poland, that Hitler informed Unity that it was time for her to take her life. A month later, after the war had begun, she shot herself in the head in Munich’s Englischer Garten. But she survived, and Hitler had her and her hospital stretcher put on a train to Switzerland. From there she was transported back to England, where she died in 1948 – three years after her beloved Führer had effected his own translation from this world to the next.