Laura Ashley built a commercial empire upon romantic fabrics and a line of cleverly tweaked “traditional” English clothing. This autumn, 65 years after the business was founded, her name still summons up images of puffed sleeves and bows in pretty floral prints. The company’s private archive, opened this week to the Observer, is a compendium of the designs and patterns that chart the changing desires of British women.

Ashley’s dresses, sold with the help of soft-focus, bucolic photographs of young women swishing through corn fields in floppy hats, located a nostalgic thread running through British taste. It is a look that has gone on to inspire other leading British designers, from Cath Kidston’s quaint domestic wares, to the homely pottery of Emma Bridgewater.

The design company – which now faces turbulent trading conditions – was the first high street chain to market an ideal of countrylife to modern shoppers. In the 1970s, Ashley’s trademark flowing flowery frocks chimed well with a hippie impulse to reject city sophistication. But the fashion house, run by Ashley alongside her husband Bernard, went on to peak in popularity in the following decade, with its industrial output of fitted velvet evening wear and sailor-collared shifts.

Just as Mary Quant had fed women a vision of the sleek technological age with her monochrome mini dresses in the early 1960s, so Ashley’s dreamy designs offered an imagined memory of a safer past. And when a brasher mood began to take hold in the 1980s, Ashley adapted by steering towards a crisper, posher look.

In 1982 style commentator Peter York identified the phenomenon of the “Sloane Ranger” in the handbook he co-authored with Ann Barr. York had noticed the pin-tucked white shirts and traditional pearl necklaces favoured by upper middle-class women near London’s Sloane Square. Laura Ashley’s skill was to quickly cater to the needs of all those aspiring Sloanes with less money to spend.

And yet the designer herself, who was born in Dowlais, Merthyr Tydfil in 1925, was not originally a fan either of frills or lace. She preferred the starched cotton pinnies and plain linen workwear that had surrounded her during her strict Baptist, Edwardian-style childhood.

“She grew up in quite a disciplined household and that kind of simple clothing really meant a lot to her,” said Imogen Hunt, the archivist who looks after the company’s increasingly treasured catalogue of patented Ashley fabrics and dress designs. An early love of quilting, Hunt explained, first drew Ashley towards her lifelong concern with reviving old prints and patterns. The tiny floral designs on the antique quilts she wanted to recreate were no longer being manufactured, so Ashley made her own.

Later, after a £10 silk screen, some dyes and a few yards of linen had been laid out on the kitchen table of the London flat she shared with Bernard in Cambridge Street, Pimlico, Ashley began to print headscarves, napkins and tea towels. Most were decorated with the kind of Victoriana – music hall playbills and penny farthings – that was becoming all the rage.

In 1955, a former coaching house in Kent produced the Ashleys’ first factory-made fabrics. Before long, they expanded and moved manufacturing to Carno, in a remote part of mid-Wales. In 1968 the couple, now parents of four children, opened their first shop in Pelham Street, South Kensington. Within a decade they had more than 70 shops across the world and a turnover of £25m.

A series of beguilingly “natural” promotional shots taken by Jane Ashley, their eldest child, peddled the company’s dream during this era. “There was a strong work ethic in the family. Business was discussed at every mealtime. My parents had a real can-do ethos,” she has recalled.

Her amateur style of photography conveyed the idea that real people were wearing these old-world outfits. Using friends as models, Jane snapped the maxi-length cotton dresses and broderie anglaise blouses that were to make her parents multimillionaires. Among her portfolio is a striking, unused image of one of her friends in an uncharacteristic Ashley halter-neck red jersey dress. These punk-influenced shots, taken near the Roundhouse in north London, were judged as not in keeping with the brand’s tone.

The billowing dresses Ashley produced in the 1980s, once Jane had left the company, are also now enthusiastically collected by vintage connoisseurs. This softer look is typified by the innocent advertising image of a young Kate Moss in a cotton wedding dress.

But in 1985, the Ashleys’ joint success story ended abruptly when the designer died suddenly at 60 of a brain haemorrhage after falling downstairs in her daughter’s house. By then, the business, which had 220 shops in 12 countries and had expanded into home furnishings, was on the brink of flotation on the stock market, where it was valued at £200m. The flotation went ahead and within five years Sir Bernard Ashley, as he had become, had sold on the company to foreign investors. The fortunes of the brand since then have been varied.

Home furnishings, wallpaper and paint, all made at the company’s factory in Newtown, Powys, have become the centre of the business since Malaysian owners took over the company in 1998 and now account for about 80% of its sales.

Earlier this year, the company issued a profit warning. Like many British firms it has been hit by currency movements in the wake of the Brexit vote. Last year it also hit the headlines when Laura Ashley’s chairman, Khoo Kay Peng, and his wife, the former Miss Malaysia Pauline Chai, settled a lengthy divorce battle. In April 2017, the 78-year-old Khoo, who with his company, MUI, owns about 60% of Laura Ashley, was ordered to pay his ex-wife £64m.

This summer the company took another financial blow following charges made on the sale of its HQ in Singapore, slashing its profits.

The Ashleys’ famous chintz reproductions have been on a long journey since the designer spotted a new trend for cotton headscarves inspired by Audrey Hepburn’s character in Roman Holiday. The couple were on an Italian holiday in 1952 when they hatched a plan to make similar scarves at home in Pimlico.

Some might wonder why the company has not kept a firmer commercial hold on a market for nostalgia that it helped to invent. Yet the powerful influence of Laura Ashley’s heritage look certainly marches on.

1960s

Mary Quant, pop art simplicity, with hot pants and mini skirts

1970s

Barbara Hulanicki’s Biba, with its Indian-inspired bohemia, and the psychedelic designs of Zandra Rhodes

1980s

Laura Ashley’s heritage dream and the subversive street looks of Vivienne Westwood

1990s

LK Bennett’s working girl’s clothing and the urban chic of New York’s Donna Karan