Once upon a time, Nicolas de Stael -- that elegant and passionate 1950s art star -- was regarded as a savior of School of Paris painting. He surely looked the part. His eyes were dark, his figure lithe, his grace aristocratic. Everyone could see he was a painter through and through. Wise men sang his praises. Washington's Duncan Phillips, the first American museum man to buy a de Stael canvas, thought him "the most gifted, the most influential, and the most painterly" of Europe's younger artists. Critic Tom Hess called him "brilliant." Scholar Douglas Cooper, going even further, would soon eulogize de Stael as "the truest, the most considerable, and the most innately gifted painter who has appeared on the scene in Europe or elsewhere during the last twenty-five years."

His rise was meteoric. So too was his fall.

In this country in the '50s painters by the hundreds followed his example. They applied their paint with trowels, simplified their forms, flirted with the line between depiction and abstraction, and called upon the subtleties of somber shades of gray.

Once everyone discussed him. Most younger painters nowadays barely recognize his name.

Why has he been forgotten? What happened to his fame?

Such questions hang like clouds above "Nicolas de Stael in America," which opened yesterday at the Phillips Collection. Curator Eliza Rathbone has forged an exhibition just right for this color-oriented, France-admiring personal museum. Its catalogue is fine. It includes some superb pictures. And yet it's not a triumph. Something thwarts its spirit. The grays that rule its paintings remain darkened by one's doubts.

De Stael (his name is pronounced "Stahl") was born to wealth and luxury, and then nearly starved to death. He joined the Foreign Legion and saw service in Tunisia. The tale of his childhood suggests a book by Tolstoy, that of his youthful poverty a scene from "La Bohe`me." His death evokes the suicides of Gorky, Rothko and van Gogh.

At his birth in St. Petersburg, in January 1914, he was appointed to become a page in the Imperial Court of Czar Nicholas II. His mother, Lioubov Berednikoff, had grown up in a palace on the Nevsky Prospect. His father, Baron Vladimir Ivanovitch de Stael-Holstein, an army major general, was deputy governor of the fortress of Peter and Paul. The revolution ruined them. Both parents died, in exile, before Nicolas was 8.

"Stael," recalls John Richardson in his memoir in the catalogue, "made an unforgettable first impression. Who on earth was this Tartar giant, I remember thinking." The painter seemed a blend of excess and restraint. He ate, drank and laughed prodigiously, yet his manners were impeccable. Cooper called him "the only aristocrat I ever met who knows how to paint."

"He was right," adds Richardson. "Since proletarian or bourgeois {origins} are adduced to explain this or that trait in a painter's makeup, there is no reason to leave a noble birth out of account. And I think the fastidiousness and cool Baudelairean dandyism of his style and the cavalier dash with which he attacked the canvas can be attributed to an attitude that was essentially aristocratic. ... Nor should we forget the other side of the coin. Stael was one of the very few modern artists who actually starved -- not so much during his early years as an orphaned refugee, but during his late twenties when he lived on next to nothing in Nice and his first wife contracted tuberculosis. Like many another White Russian, Stael was too proud and fatalistic to hold this against the world. Nevertheless, the scars went deep. I cannot do better than quote Cooper's characterization: 'He was a complex and in many ways contradictory character: autocratic, exuberant, morose, charming, witty and uncompromising. ... He lived out his life between a series of violent extremes. ... Pride would suddenly be replaced by humility, indulgence by asceticism, exaltation by gloom, uproarious laughter by withering scorn, supreme confidence by serious doubt, excessive work by deliberate idleness, great poverty by riches.' "

De Stael, as a young man, had won prizes as a fencer. "One of his few boasts," writes Richardson, was that he'd saved the life of the School of Paris master he admired most (he had visited Georges Braque, and found the frail painter choking on the floor in time to summon help). De Stael fought fiercely for success, and eventually achieved far more than he had dreamed of -- and then, at 41, on March 16, 1955, he hurled himself to death from the terrace of his seaside studio at Antibes.

You'd think the story of his life would be more than enough to secure his lasting fame. But it hasn't really helped.

The finest of his paintings here both welcome and withstand the fiercest competition offered by the masterpieces hanging at the Phillips. De Stael's "Large Orange Nude" (1954), an odd apotheosis of the "Olympia" of Manet, may be the most imposing, but there are a dozen others comparably impressive, his "Poppies," for example, with their beiges lit by brilliant reds, or his flat yet forward-stretching vision of "The Road" (1954), or his dark and dreamlike rendering of his studio table, painted the same year. His seascapes in particular -- say, his "Port of Dunkirk" or his "Square Fort at Antibes" -- linger in the memory, and despite their tough modernity somehow pull you back through Manet to Courbet.

Perhaps that is their problem now, though once it was their claim to fame. What may be his finest paintings, those he produced in the last years of his brief career -- having chosen to abandon nonrepresentational abstraction -- may well strike Americans as too domestic in their scale, too traditional in subject, too subtle in their nuances, just a bit too French.

Paris, until the end of World War II, was viewed by most Americans, with both awe and envy, as the crucial cradle of new painting. "Paris," announced New York critic Clement Greenberg in 1946, "remains the fountainhead of modern art, and every move made there is decisive for advanced art elsewhere." France, that land of masters, was liberated now from Nazi occupation, and surely its young painters, those heirs of Manet and Monet and Cezanne, of Braque, Matisse, Picasso, would show themselves as giants soon and lead the world again. At least that was the hope, or perhaps the fear. Then suddenly things changed.

Though almost no one had foreseen it, suddenly America, and especially Manhattan, had seized the art world's spotlight. What followed was a battle. On one side were the new New York action painters, Pollock and de Kooning, Gorky, Rothko, Kline, those daring pioneers who had plunged into abstraction and let their brushes fly and filled the walls of galleries with works that seemed amazingly heroic, raw, courageous, and astonishingly big. The young Frenchmen who opposed them -- Soulages and Riopelle, Tal Coat and Hans Hartung, and young Nicolas de Stael -- suddenly began to seem a little bit too delicate, too small and too sweet. "Despite their seeming convergence," Greenberg would observe in 1953, "there are crucial differences between the French and the American versions of so-called Abstract Expressionism. In Paris they unify and finish the abstract painting in a way that makes it more acceptable to standard taste."

"More acceptable to standard taste." What complaint could be more crushing? By the last years of the '50s, with Pollock now a martyr, and de Kooning newly rich, and with Stella, Johns and Rauschenberg glimpsed on the horizon, New York's victory seemed total. You could feel it in the market, and in the chauvinistic boastings of our most imperial critics. Paris had been beaten! America had won!

De Stael, though he benefited briefly from the transatlantic competition, was one victim of that war.

His bricklike blocks of paint, thickly troweled on the canvas, though certainly much bigger than the paint-pats of Cezanne, seemed tiny in comparison with the giant gestures of Franz Kline. His distrust of hard-edged shapes -- he scorned "geometricians" -- made him seem old-fashioned. So did the scale of his paintings and the subjects of his art.

The titles of his pictures -- "Ballet," "Toreador," "The Artist's Table," "Still Life, Flowers" -- had suddenly assumed a 19th-century ring. The heroes of the moment were painting pure abstractions. But de Stael, though he'd tried abstraction first, began to paint from nature after a revelation in 1952. His epiphany occurred in the Parc des Princes, Paris, at a floodlit soccer game that pitted Sweden against France. "Between sky and earth, on grass that is either red or blue, there whirls a ton of muscle in complete disregard for self with, against all sensibility, a great sense of presence," he wrote to his old friend, the poet Rene Char. "What joy! Rene, what joy!"

"All painting has a subject, whether one wishes it or not," he said. Let those artists he dismissed as "le gang de l'abstraction avant" paint their pure abstractions, their airy, empty fields. He, instead, would show us dancers, trees and nudes, flower vases, harbors. He'd keep looking at the world, at the red sea and the violet sand. He'd give his paintings weight. He would paint the world he saw.

Duncan Phillips loved that stubbornness. He loved de Stael's colors too, and the toughness of his markings, and his loyal and unswerving devotion to the great French tradition. He purchased de Stael's pictures early, eagerly and often. "De Stael," writes Laughlin Phillips, "perfectly fit Duncan Phillips's personal standards of artistic excellence. He responded intensely to visual experience, with a fresh and unique way of seeing. Virtually all of his work was directly grounded in his vision of nature."

Faddishness distressed both the painter and his patron. "There are only two valid things in art," De Stael once wrote: "1) the lightning flash of authority, 2) the lighting flash of hesitation. That's all."

That love of hesitation, a constant in his work, hurt his reputation too. De Stael's trust in doubt, in slow consideration, is seen in every picture in the Phillips exhibition. An Andy Warhol he was not.

But nor was he a Cezanne, a Braque or a Vuillard. He must have understood that he was born too late to be remembered with the masters of School of Paris painting. His markings feel like chunks of stone. There is about his art an odd, disturbing heaviness, a sense of soaring blocked.

One feels it in his paint, one feels it in his gloom. At the height of his success, he was writing to his friends of the "atrocity" of his solitude. He wrote, "to bore oneself so much... ."

His eyes ached, he complained. He became incapable of sleep. "I don't have the strength," he wrote a friend on March 16, 1955, "to complete my paintings." Later the same day, he threw himself to the rocks below.

Eliza Rathbone believes the time has now arrived for a "reconsideration" of de Stael's achievement. His influence was real. One sees that in his collages, which feel like Robert Motherwell's, and in the way his marking and his colors inspired Richard Diebenkorn, among many others. But this show will not greatly change posterity's opinion. Someday his best pictures may be taken from the storerooms and be seen once again in America's museums. And someday his competitors, the abstract painters of New York, may fall, as he has, out of fashion. But that time has not yet come.

The Phillips exhibition, "Nicolas de Stael in America," has a slightly awkward title. Though almost all its pictures have been borrowed from American collections, he never painted in this country. Eliza Rathbone's show will visit the Cincinnati Art Museum after closing here Sept. 9.