“This photo of Queen Elizabeth, the Queen Mother, is the very first sitting Beaton had with a member of the reigning royal family. It was taken in July 1939, a few months before the war, and was done to celebrate the Queen’s white wardrobe, which was designed for a state visit to Paris a year earlier. Her mother had died five days before this tour, but and the visit was an important diplomatic visit they couldn’t cancel despite being in mourning. She couldn’t wear black, so Norman Hartnell designed this wardrobe of white crinoline gowns that became a sensation and set London up as a fashion rival to Paris. Beaton arrived for the sitting and was told he had 20 minutes with her, but three and a half hours later they were still going and having a fabulous time. He invested the royal image with a real magic and romance.”

“This is Princess Margaret in front of a tapestry at Buckingham Palace. This was taken in 1951 to mark her 21st birthday. It was her second independent sitting with Beaton and was designed to showcase her as a young woman and rebrand her after the childhood images during the war. It shows her as incredibly glamorous and stylish; during the fitting she wore three different gowns, including this one designed for her by Christian Dior. It also balances that idea of tradition and modernity. Margaret symbolizes change and progress to ensure the monarchy remains relevant.”

“This is Princess Marie Louise of Schleswig-Holstein, one of the granddaughters of Queen Victoria. She’s a real connection to a bygone era and is making this priestly gesticulation. It’s an off-the-cuff snap that Beaton didn’t show to her because he was worried she’d find it undignified, but he published later. She’s considered quite eccentric, but he’s completely enchanted by her. The image feels very contemporary for the moment it was taken, in the year of the Queen’s coronation, and there’s something spectacular about a woman who connects to the Victorian age in an incredibly modern, striking picture.”

“This is one of the later photographs, taken at the end of October in 1968. This photograph was initiated by Beaton, who by this point felt comfortable suggesting commissions. He was about to open a seminal exhibition at the National Portrait Gallery, the first time a photographer and a living artist was shown, and he wanted material of notable names. What’s lovely about this photograph is that the Royal Family then decided to use it to mark the official engagement in public life of Prince Charles, who was 20 years old here. Beaton was quite disappointed with his performance. He was unwell at the time and there was dreadful weather, so he ended up recycling compositions he’d used in a sitting from several weeks earlier with the Queen. But the result is that you have this series of photographs of monarch and heir that reinforce a sense of stability of the royal line; here they are photographed in a similar guise. Beaton never got on with Prince Philip very well, but Charles warmed to him and you can see that.”