In the beginning, there was red wine. And for a while that was about it, unless you were one of those mead drinkers—who frankly probably smelled bad and had altogether too much hair.

For those with slightly more refined tastes, wine was a simple affair made of fermented grapes. There wasn't a whole lot of wrangling about varietals or aging or any of the stuff we worry about now. Folks smashed together pretty much whatever grapes were growing around their fiefdoms, and called it good.

Fast forward a few hundred years to the sunny slopes of California where a vigorous vine of uncertain origins called Zinfandel grew. How it got here, no one knows. Though it was first a blending wine, favored in Italian immigrants' field blends, folks eventually got a taste for it all by itself (or at least mostly so). Spicy and hot, bold and juicy, Zinfandel slowly became known as a uniquely American grape that made a uniquely American sort of wine. Suffice it to say, you probably won't be finding any French Zinfandels hanging around the Bottle Barn.

The grape flourishes in the warm, Mediterranean climate of inland California vineyards (an early hint to its true origins). Thousands of acres were planted in places like Dry Creek and Napa, and thousands of acres of old vines, many more than 90 years old, became highly prized for their mature, concentrated flavors. Zin became the kind of big, bold wine that people said might go well with bold, spicy foods like pizza and tomato-laden Italian foods (ding!—another hint).

In the late 1990s, despite its questionable past and unfortunate relationship to its paler and sleazier sister, white Zinfandel, the varietal (not the white kind, but the red), became the grape of the moment, spawning its own fan club. Known to each other as members of ZAP, or the Zinfandel Advocates and Producers, these happy folks decided to throw it a party each year in San Francisco and have hundreds of its producers and fans come together and drink heavily of the bad boy of wine. And it was good.

Today, Zin is suffering a slight public-relations problem due to its skyrocketing alcohol levels (though it is not alone in this issue) of up to 16 or 17 percent. Some restaurateurs have even started banning the higher-alcohol versions, because they're difficult to pair with food and get people pickled mighty fast. Better vineyard management, however, and an awareness of the problem should shake things out, putting Zin back on its rightful pedestal as a truly American wine. Sort of. The postscript to the story is that after a whole lot of DNA-testing, scientists think that Zin is actually an Italian varietal brought over to the New World hundreds of years ago. But you knew that, didn't you.

Local Zins to watch for: Ravenswood, Rosenblum, Seghesio, Ridge, Pedroncelli, Rafanelli, Bella, Carol Shelton, Dry Creek, Lambert Bridge. This year, ZAP meets Jan. 25-28 in SF. www.zinfandel.org.

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