Margaret Howard, Daisy Leiter, 1898 [English Heritage]

HER gaze has borne down on many a visitor over the years: Daisy Leiter’s portrait has been in situ at Kenwood for decades, her nine-foot high image hung on a staircase.

The American heiress, painted by John Singer Sargent, was once described as “Daisy with the violet orbs… the loveliest eyes in Washington.”

Sargent captured Daisy’s eyes in oils when she was aged 19, in 1898 – and now Daisy has been joined at Kenwood by 18 other “Dollar Princesses”, as they were dubbed at the time, in a new exhibition organised by the Friends of Kenwood and English Heritage.

It is the first time the images have been gathered together, and some have never been seen in public before.

The Dollar Princesses were a sometimes maligned group that came to prominence in the late 19th and early 29th centuries – and who Sargent would be the go-to for the grand portrait.

The phenomenon – which PG Wodehouse would later parody in a number of comic novels – saw American heiresses, whose families had made fortunes in the new world, marry British aristocrats, often families whose wealth was increasing tied up in the creaking bricks and mortar of ancestral piles and needed a fresh income to draw on.

While Society movers and shakers, and often portrayed as It Girls and proto-celebrities at the dawn of mass media, the Dollar Princesses each have a fascinating story behind the gaze captured by Sargent.

Behind each wonderful picture is an equally engrossing story, and curator Dr Wendy Monkhouse has had the task of tracking down the paintings and studies from across the world – and then trying to bring alive the biographies of the faces that look down from the walls of Kenwood.

Dr Monkhouse said: “Dismissed historically as ‘Dollar Princesses’, their stories were far more complex than that throwaway label.”

Edith, Lady Playfair, 1884 [Museum of Fine Arts, Boston]

Having them all gathered in one place for the first time feels like you are gatecrashing a party in an F Scott Fitzgerald novel – a fact not lost on Dr Monkhouse.

She said: “We have tried to look at who they were – what they did, and trace their individual stories and journeys.

“It wasn’t just one story of cash for coronets. We wanted to put that to bed. There is all the grandeur – the tiaras, the fast cars, the aeroplanes, helicopters, there were racehorses to breed – all the trappings that wealth brings.

“But there were political activities, committees, work. There were happy and failed marriages, complex social mores to adhere to.”

Daisy moved to Wiltshire aged 25 when she married Henry Howard, the 19th Earl of Suffolk, who would be killed in the First World War. In Wiltshire she was involved in promoting local industries such as lacemaking, and was a keen horse rider. Their marriage was – unlike some of the trans-Atlantic betrothals – welcomed by the gossip columns: “The ‘World’ concludes that Lord Suffolk is one of the best fellows in the world, and worthy of one of America’s best daughters,” gushed the Daily Express in 1904, adding: “this is a most unusual newspaper attitude with regard to American marriages into the peerage”.

Alongside Daisy – who would, among, many other things, become a helicopter pilot – is an image of Jessie Wilton Phipps, who Sargent has captured wearing pearls, diamonds, gold and a black and white striped corset.

Her story reveals the range of the Dollar Princesses: she became a member of the London County Council, a campaigner for the blind and would be awarded a damehood for her public service.

The trend saw around 500 American heiresses married into the British aristocracy over a 30-year period.

Some, like Daisy and Suffolks, were successful.

Mary Crowninshield Endicott Chamberlain had her portrait painted in 1902 and her domestic story is much happier than the unfortunate Consuelo.

Viscountess Astor, 1908 [National Trust Images, Matthew Hollow]

Mary Endicott grew up in Salem, and met politician and manufacturer Joseph Chamberlain at the British ambassador’s residence in Washington.

Chamberlain was wealthy in his own right and there was a mutual attraction. She would become his unofficial political secretary.

“Really, he is charming and very attractive and agreeable,” she would write to a friend during their courtship. But others were a disaster from the off. Conseulo Vanderbilt, the Duchess of Marlborough was betrothed very much against her wishes to the Ninth Duke of Marlborough – who admitted to her he was only marrying her because her family wealth would save Blenheim Palace. She was said to have wept tears beneath her wedding veil.

A charcoal by Sargent in later and happier times has never previously been seen in public.

The exhibition marks the centenary of Sargent’s death and as well as the grand oils that draw on Kenwood’s earlier masters such as Joshua Reynolds, and the sitters’ airs of Restoration princesses or Georgian ladies, the show brings Sargent’s later studies in charcoal.

They reflect the designs and fashions of the Edwardian period – bob cuts and curls, less fussy clothing and a sense of the freedoms of the Suffragette age.

The show has been helped by the fact the world’s most pre-eminent Sargent expert sits on the Friends of Kenwood board – Richard Ormond.

He is the artist’s great nephew and his help was invaluable as Dr Monkhouse embarked on a two-year treasure hunt as they scoured the globe for examples.

Mary Crowninshield Endicott Chamberlain [English Heritage]

“We drew up a long list and set out to find out where they were,” she says. “Once we had found a portrait, we then had to persuade the lender why their painting should travel halfway around the world. But the idea was a compelling proposition. They were very generous.”

The images reveal how Sargent developed as an artist.

“Sergeant had an amazing cocktail of influences,” Dr Monkhouse adds. “He trained in Paris in the 1880s and was inspired by Diego Vasquez and Edouard Manet, while also drawing on early influences that have a very Kenwood feel – Sir Joshua Reynolds, for example.

“There was something very American about the pictures – confident, powerful, new. But stylistically, some of the images make you think of Gainsborough, and some of the content might make you think of Rembrandt.

“What Sargent did was take these elements and bring them together, and then modernise them.”

Sargent was friends with many he painted.

“He was well connected with both the Americans and the British elite,” reflects Dr Monkhouse.

“He lived in the heart of Chelsea, and many of his subjects were neighbours. And the social networks of the time were powerful and effective. He would be passed on from one family to the next who wanted portraits, recommended to friends. The women all knew each other, worked together on committees, socialised in the same circles.

“Sargent, the pre-eminent portrait artist of the time, captured their characters.”

• Heiress: Sargent’s American Portraits runs until October 5 at Kenwood House, Hampstead Lane, NW3 7JR. Open daily 10am-5pm. Admission to the house is free, however there is a charge for the exhibition. Members get free entry. www.english-heritage.org.uk/kenwood