A worker picks grapes at a vineyard in California’s Napa Valley in 2008. Robert Galbraith / Reuters

Paris has lent its name to some of history’s important international moments. There was the Treaty of Paris, which ended the war between Great Britain and the United States, and, much more recently, the Paris agreement, which last year committed almost every country in the world to addressing climate change. In between those two, there was the so-called Judgment of Paris, the outcome of which was once described as a “vinous shot heard round the world.”

On May 24, 1976, a group of French wine experts gathered in the capital for a blind wine tasting. The event was organized by Steven Spurrier, a British sommelier who ran a wine school and shop in the center of town. American visitors had brought him wine from California, and Spurrier became curious to see how it would stand up to French wines, regarded as the best in the world. Spurrier and the judges, as well as other sommeliers and observers, went into the tasting thinking the California offerings didn’t stand a chance, and that the tasters would be able to discern the flavors even when their identities were hidden.

But that’s not what happened. Here is the dispatch from the only reporter present at the tasting, George Taber of TIME magazine:

As they swirled, sniffed, sipped and spat, some judges were instantly able to separate an imported upstart from an aristocrat. More often, the panel was confused. “Ah, back to France!” exclaimed Oliver after sipping a 1972 Chardonnay from the Napa Valley. “That is definitely California. It has no nose,” said another judge—after downing a Batard Montrachet ‘73. Other comments included such Gallic gems as “this is nervous and agreeable,” “a good nose but not too much in the mouth,” and “this soars out of the ordinary.”

When all that swirling, sniffing, and sipping was over, the judges had picked reds and whites from little-known wineries in California’s Napa Valley over ones from France’s renowned Burgundy region as the winners of the taste test. A 1973 Stag’s Leap Wine Cellars Cabernet Sauvignon bested a 1970 Chateau Mouton-Rothschild and three other Bordeauxes. A 1973 Chateau Montelena topped a Meursault Charmes Roulot of the same year. Two other California Chardonnays also ranked higher than their French counterparts.

“The irony for the French was the inability of the tasters—all of impeccable credentials—to distinguish the origins of the wines,” wrote Barbara Ensrud in The Wall Street Journal in 2001. “They picked the wines they liked best, certain that because they were judged the best they had to be French.”

The results baffled French winemakers and vindicated their Californian counterparts, who were not well-known even to wine-lovers in the United States. Here’s Ensrud:

Though it may seem improbable to young wine drinkers of today, at this time 25 years ago California wines—except for half-gallon jugs and a stray Cabernet or two from the demotic labels of Inglenook or Christian Brothers—were virtually unavailable outside the Golden State. California wines were so little known in New York—not to mention the rest of the world—that the Four Seasons Restaurant launched a spring gala in 1976 to introduce them to New York’s wine and food community.

California wines were suddenly in demand. Ensrud again:

Phones at Chateau Montelena and Stag’s Leap wineries rang nonstop for days. Only two weeks earlier, Warren Winiarski, proprietor of Stag’s Leap Wine Cellars, had tried to get a New York wine merchant to stock his wines, without success. “Why should I buy your wine when I can get Chateau Gloria for the same price (about $7)?” he was asked. The day after the news broke, the retailer called, avidly trying to get Mr. Winiarski to sell him everything he had.

The mythic tasting was such a dramatic milestone in the history of winemaking that Hollywood turned Taber’s book on the tasting into a movie starring Alan Rickman, Bill Pullman, and Chris Pine in 2008.

California wines won out in a rematch in 1978, and again in a tasting for the 10th anniversary of the Judgment of Paris. The same happened during a reenactment in 2006 in honor of the tasting’s 30th anniversary. The Times wrote back then:

Despite the French tasters, many of whom had taken part in the original tasting, “expecting the downfall” of the American vineyards, they had to admit that the harmony of the Californian cabernets had beaten them again. Judges on both continents gave top honours to a 1971 Ridge Monte Bello cabernet from Napa Valley. Four Californian reds occupied the next placings before the highest-ranked Bordeaux, a 1970 Château Mouton Rothschild, came in at sixth.

A delighted Paul Draper, the Monte Bello winemaker, said: “Maybe it is final justification that it held through all these years and did well.”

Today, California produces 90 percent of U.S. wine, according to the Wine Institute, an advocacy group for the state’s winemakers. The United States is the fourth-largest wine producer in the world, behind Italy, France, and Spain.

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