And worst of all was his popularity, which for much of his life was enormous. Until the other Andy came along — Andy Warhol — Wyeth and Norman Rockwell were without doubt the two most widely recognized names in American art. Wyeth's museum shows were blockbusters and his sale prices strong, especially after the Japanese discovered him in the 1980s.

Even when Wyeth is admitted into the canon, he's held a bit at arm's length. The Museum of Modern Art in New York City owns his most famous canvas, Christina's World, which it acquired in 1948, soon after it was painted, for just $1,800. But while the picture is always on display at MoMA, it's consigned to what you might call an anteroom on the margins of the more respectably modern galleries, a salon des refuses that it shares with Edward Hopper's House by the Railroad. Seeing Christina splayed across her field of grass, gazing toward that house on the horizon, it's easy to imagine that it's the citadel of MoMA she's looking at so poignantly, the place she still has not entirely entered, even if she is inside.

It's true that the discoveries of Picasso and Pollock don't much ruffle the grave surfaces of Wyeth's work. For much of his career he painted not only in watercolors but in tempera, a pigment and egg-white medium that predates oil paint. His only art school was the Chadds Ford home he grew up in. His father was the greatly gifted illustrator N.C. Wyeth, whose thronged imaginings of scenes from Treasure Island and The Last of the Mohicans made him rich and famous. He decided early on that his talented son should also be an illustrator and set him to work hard at it from his teens.

Andrew Wyeth's skills as a draughtsman — and maybe also as a showman — are owed to his boisterous, demanding father. But the quiet and spareness of his pictures, the sense of longing and abandonment, of having exacted the maximum effect from the minimum means, may be a reaction against his father's swashbuckling art. His father also marked Wyeth's life strongly in one other way. In 1945 the elder Wyeth, along with his 4-year-old grandson by Andrew's brother Nat, was killed when his car stalled on a railroad track. It was an event that Wyeth's biographer, Richard Meryman, says split Wyeth's life in two, so that he spent the rest of it "processing the first 28 years — a long, unraveling of love and guilt and rage."

Whatever the reason, there's a spareness and gravity in Wyeth's art after World War II that would be his trademark for the rest of his career. His landscapes are more astringent and cooler. His portraits too. The people in those portraits are known to him. Most of them are family, like his son Jamie, who also became an artist, or neighbors like Karl and Anna Kuerner, a German-American couple he painted many times in Chadds Ford, and Christina Olson, the crippled woman in Christina's World whom he knew from around his summer home in Cushing, Maine. But though these people are his familiars, they look to us enclosed, subdued, even solemn, always keeping something of themselves to themselves.

Wyeth's famous "poetry," when he arrived at it, always had something to do with a mood of almost palpable quiet — the quiet you find so often in Hopper, but without Hopper's way of making sunlight unnerving or that little thrill of voyeurism that Hopper liked to provide. Wyeth's people may not be looking back at you, but, Christina's World aside, you rarely get the feeling they're being watched unawares.

And though Wyeth might occasionally paint a dog sleeping sweetly on a bed, the comical cheer of Rockwell is not for him. What people mean when they accuse Wyeth of sentimentality is not that he gets cute, but that the world we see in his paintings seems like a place we might long to inhabit sometimes but don't actually live in. And the people he shows us — with their Yankee rectitude, the weathered parchment of their faces and their Nordic inwardness — seem to inhabit some prelapsarian America, the one that existed before automobiles and television. Wyeth's popularity coincided with the disappearance of an older U.S., a nation of regions, localities and rural fastnesses that was overwhelmed and homogenized after World War II by the mass market and mass media. Which is why, even at their dryest and gravest, his pictures are inevitably flush with nostalgia.

Meanwhile, in his life, Wyeth was not quite the simple yeoman of Chadds Ford. The people he painted might look as though they got around in oxcarts, but by the 1970s Wyeth was driving an ultraluxe black Stutz Bearcat limo, a car he had in common with Elvis and Frank Sinatra. He was good at giving self-aggrandizing interviews and had a gift for self-promotion that came to a head with the curious case of the Helga pictures. Those were a cache of 240 paintings, watercolors and drawings, some of them nudes, that Wyeth had made between 1970 and 1985 of a typically subdued, slightly Rubenesque young blonde woman. In the summer of 1986, the New York Times reported on its front page that an American collector named Leonard Anderson had paid $6 million for these previously "unknown" works.

Soon it emerged that the woman was Helga Testorf, a married housekeeper for Wyeth's sister Carolyn in Chadds Ford. Wyeth's wife Betsy claimed to have known nothing about the pictures. When she was asked what she thought was the motive behind them, she offered a melodramatic one-word reply: "Love." However they came to light, their "discovery" and the suggestion that they represented some secret love affair was news that got them on the cover of TIME and Newsweek and then a big exhibition at the National Gallery of Art in Washington.

Andrews, it turned out, was not actually a collector but a publisher of newsletters. ("Swine Flu Litigation Reporter" was one of them.) He was also a greeting-card manufacturer who had secured all reproduction rights to the Helga pictures. After the publicity storm had been whipped to a peak, he sold the whole bunch to a Japanese buyer for a reported $45 million. At that point, Wyeth found it prudent to come forward to say there had never been a sexual relationship between him and his model, and his wife announced that actually she had seen some of the pictures before, though not most of them.

But Wyeth won't be remembered for the dubious moment of Helga. It's all those other quiet, elusive canvases that will stay with us. The canons of art history have loosened quite a bit in recent decades, enough so that no full picture of the modern world can exclude what he did. Who knows? Someday MoMA may even bring Christina all the way in from the cold.

Copyright © 2009, Time Inc. All rights reserved. Reprinted by permission.