Queen Elizabeth as Aladdin...Really! See the Costume from Her Early 'Acting' Years

Queen Elizabeth has lived her life on the world stage, but in her early years she performed on a much smaller one, too.

As a teen, the then-Princess Elizabeth loved to entertain her family and friends – and, alongside her younger sister Princess Margaret, would take part in pantomime shows at Christmastime.

One of those costumes, from a 1943 performance of Aladdin in which she played the title role, will soon be on display starting September 17.

Part of Fashioning a Reign: 90 Years of Style from the Queen’s Wardrobe, the Aladdin clothes are among more than 30 outfits at Windsor Castle representing key moments in the Queen’s life and reign.

The pantomime performances took place during WWII, a period when Elizabeth and Margaret largely lived at Royal Lodge on the grounds of Windsor Castle. Their Christmas shows from 1941 to 1944 were staged in the castle’s Waterloo Chamber for fun and also to raise money for the Royal Household Wool Fund, which supplied knitting wool to make comforters for soldiers fighting at the Front.

According to the Royal Collection, which oversees the annual opening of the palaces, Elizabeth and Margaret helped make the Aladdin costumes themselves. Elizabeth, then 17, wore a silk tunic and silk-satin embroidered trousers, while Princess Margaret (as Princess Roxana) was dressed in a crimson silk-satin jacket trimmed in gold and crimson brocade with a matching long silk dress. The Emperor’s costume, the curators reveal, was made out of furnishing fabric probably once used in Windsor’s State Apartments.

The three-pronged fashion exhibition marking the Queen’s 90th birthday is also taking place at Holyroodhouse in Edinburgh and Buckingham Palace in London. The exhibit uses “fashion as the perfect barometer of the longevity of her life and the key highlights of her reign,” curator Caroline de Guitaut tells PEOPLE.

“Fashion is a great communicator in terms of changing styles and therefore changing decades,” says de Guitaut. “She is renowned for her sense of style and support for British design. It seemed to capture all of these things at once.”

Also being shown at Windsor are outfits that celebrate the Queen’s lifelong love of horses. She continues to ride in Windsor Great Park, and the exhibit will include a riding jacket, jodhpurs and black patent riding boots made for Princess Elizabeth by the equestrian and livery tailors Bernard Weatherill in 1947.

The jacket, in the style of a riding habit, is sharply cut away to allow for jodhpurs or a riding skirt to be worn underneath. There is also a hacking jacket and jodhpurs made by Bernard Weatherill in the 1980s that typifies the style of clothing worn by The Queen when riding at Windsor.

“Previous exhibitions where items from her wardrobe have been included have proved incredibly popular,” says de Guitaut. “We know its something that our visitors enjoy.”