As France’s first independent art foundation prepared for its 60th anniversary, there was an air of excitement in the village of Saint-Paul de Vence. What could possibly go wrong on a summer day in late June? Well, for starters, President Macron—who had given the exhibition “Amitiés, Bonnard–Matisse” his high patronage—would no longer be attending: he had a snap election to deal with. And the good weather, normally a certainty in the Côte d’Azur, had turned unseasonably cold and might even include rain! Could the Lenders Dinner for 400 carefully selected guests, which cleverly amplified the idea of amitiés, go ahead in the magnificent Miró Labyrinth or would it have to be moved hastily indoors? In the end, the sun shone, the new exhibition space was blessed, and the glamorous dinner went ahead. All was well.

L’Été, by Pierre Bonnard, 1917.

The Fondation was created by the art dealer Aimé Maeght and his wife, Marguerite, in 1964. Heartbroken by the loss of their son Bernard, who was 11 when he died of leukemia, they threw themselves into the project with the help of artist friends Joan Miró, Marc Chagall, Georges Braque, and the Giacometti brothers. A dialogue between these artists and the Catalan architect Josep Lluís Sert produced a building that is essentially an artwork: the immaculate modernist structure crystallizes a cultural moment as well as the Maeght family’s heartfelt belief in art.

Matisse painting the model Carla Avogadro in his Nice studio, 1942.

With so much artistic intention at its inception, is it surprising that the Fondation Maeght exerts a unique charm? It has become a place of pilgrimage and an inspiration for art lovers, who return often to marvel at the now priceless foundation and Aimé Maeght’s genius in making it happen.

An exterior view of the new Fondation Maeght extension.

“Amitiés, Bonnard–Matisse,” which is on now, consists of more than 300 loans that help illuminate the long friendship between Aimé Maeght, then an ambitious young printer, Pierre Bonnard, and Henri Matisse. A scholarly deep dive into the work of both artists, their friendship, and their response to painting in the South of France, the exhibition also sheds light on Maeght’s first commercial venture as an art dealer, Galerie Maeght.

At that time, Maeght, who was born in the north of France, was allowed to drive between occupied Paris and the “free” South; it seems his proclivity for risk was there from the start. He made hair-raising drives to Paris carrying Bonnard’s paintings, disguised with loose white slip and daub that he could later wash off, and then returned South carrying works owned by the Jewish art expert and dealer Georges Bernheim, who was hiding there and in need of funds.

A 1932 Matisse study for The Dance, a mural, at the Barnes Foundation, in Philadelphia.

Maeght was involved with the Resistance, but when the gallerist Jean Moulin, who was the local leader of the Resistance, was arrested in 1943, in Lyon, Maeght moved his young family to the quiet village of Vence and by chance took a villa next door to Matisse. So began a new friendship that ultimately led to the opening of the Galerie Maeght, on Rue de Téhéran.

Thadée Natanson et Misia, by Bonnard, circa 1906.

This summer also sees the resolution to a long-standing question: how to expand the precious fabric of the Fondation without compromising its integrity. An inventive design by the Neapolitan architect Silvio d’Ascia doubles the wall space, allowing the Fondation to present more of its legendary collection. Silvio confessed to me that as a boy he used to sketch the Fondation’s Giacometti Courtyard, and it is from under this courtyard that he removed over 4,700 square yards of earth, rebuilding it with a forensic attention to detail. D’Ascia resisted the temptation to “épater les bourgeois”—to create something shocking—and is thrilled when visitors ask him what has changed. His elegant and discreet whisper, so different from the sensation caused when the Fondation first opened, suggests that 60 years later this avant-garde jewel is now a bedrock of France’s art establishment.

“Amitiés, Bonnard–Matisse” will be on at the Fondation Maeght, in Saint-Paul de Vence, until October 6

Sarah Hyde is a London-based writer