PARIS — Collecting and preserving fashion was, for Azzedine Alaïa, about more than archiving his inspirations. It was a “cooperative attitude, a mark of solidarity towards those who, before me, wielded their scissors with pleasure and exactingness,” the late designer once said. “It is my tribute to all the trades and all the ideas that these clothes convey.”

Alaïa began collecting in 1968, when he had the opportunity to acquire exquisite pieces from Cristóbal Balenciaga when his couture house closed. He went on to amass as many as 20,000 items spanning key periods in fashion history, from the birth of haute couture in the late 19th century to the rise of innovators like Comme des Garçons and Jean-Paul Gaultier in the 1980s.

The collection, which was built almost entirely in secret, was bequeathed along with his home in the Marais to a foundation created by Alaïa to preserve his legacy. Two fashion exhibitions in Paris— at the Palais Galliera and at the Fondation Azzedine Alaïa — now offer glimpses of the sprawling collection which came to comprise the equivalent of a real-life backup disk for 20th century fashion.

In addition to being a virtuoso cutter, Alaïa was a “secret historian,” said Olivier Saillard, director of the Alaïa Foundation and the Palais Galliera’s curator. “He told me he had ‘some’ Alix Grès pieces — he had more than 1,000.”

Alaïa was fascinated by Madeleine Vionnet, as well as collecting iconic designs by Worth, Jeanne Lanvin (500 pieces), Jean Patou, Paul Poiret, Gabrielle Chanel, Elsa Schiaparelli and Christian Dior. He bought pieces from Adrian (Adolph Greenburg), and at one point owned more Chanel suits than the house itself. At the Palais Galliera exhibition, marvels such as Barbara Hutton’s costume by Balenciaga for the Beistegui Ball in Venice are displayed alongside dresses by the American ready-to-wear pioneer Claire McCardell, and coats by Paul Poiret featuring silk linings designed by artist by Raoul Dufy.

Impassioned by Elsa Schiaparelli, Alaïa bought not only her designs but documents such as wartime correspondence and pattern fabrics from her workshops.

The show features favourite designs by Alaïa’s contemporaries, too: designs by Charles James — whom he discovered in New York at the beginning of the eighties, and in whom he “probably recognised his own architectural sense of line” says Saillard — as well as Jean Paul Gaultier, Rei Kawakubo, Junya Watanabe, Alexander McQueen, Yohji Yamamoto and Thierry Mugler.

“He saved this heritage for France and for fashion. He was consumed by the idea that everything could disappear,” Saillard said.

While the Galliera exhibition covers the breadth of Alaïa’s passions, the exhibit currently on display at the Fondation Alaïa zooms into the dialogue between Alaïa and seminal Paris couturier Alix “Madame” Grès. Both designers were disciples of a certain form of deceptive simplicity, and their creations often conceal extreme complexity in cut and design. The exhibition evokes a world of mystery, beauty and extraordinary technical skill.

Just as their works in chiffon, velvet and crepe silently correspond, so do the designers’ biographies. The enigmatic Grès changed her name several times (Germaine Emilie Krebs, Alix) and even her death was hidden by her family for a year — amplifying the mystical dimension of her work. Likewise, it’s been discovered that Azzedine Alaïa was in fact born five years earlier than he claimed for decades, and changed the spelling of his name upon arriving in Paris to realise his dream.

Alaïa’s approach to fashion was intimate, instinctive, exacting. “My work consists of following, of finding the body. I find the place for a shoulder pad by feeling the bone there and there. I crumple, I pull so that it takes the shape of the body,” he said. “My pleasure is to be able to save, to make beautiful.”

The current exhibitions in Paris show the extent of the obsessive research that informed his technique. Ghosts comes alive again: just as Maison Alaïa’s collections are being revived under creative director Pieter Mulier, Saillard’s exhibitions breathe new life into the garments that have remained like sleeping beauties in thousands of boxes — even plastic bags — on Rue de la Verrerie for years.