It has to rank as one of the tastiest business screwups of our time: Jess Stonestreet Jackson, a San Francisco litigator dabbling in winemaking, made a big batch of Chardonnay in the early 1980s, and the fermentation process didn't complete, leaving the wine sweeter than intended. "It had one-half percent or so of residual sugar," recalls Randy Ullom, a wine master and one-time competitor of Jackson's. Tasting it, Jackson thought, This is actually quite nice. It wasn't off-putting. It beckoned another sip. "You didn't need a Ph.D. to understand the wine," Ullom says.

Thus was born Kendall-Jackson Vintner's Reserve, which has dominated the popular Chardonnay category ever since. The Chardonnay financed Jackson's purchase of more than 20 smaller wineries, as he assembled 14,000 acres of vineyards and became one of the industry's most influential entrepreneurs. Forbes estimated his net worth at $1.85 billion last year.

Jackson died April 21 of complications of cancer. He was 81.

In his later years, Jackson turned to horse racing and breeding, and he owned two horses honored as Horse of the Year—Curlin and Rachel Alexandra, a filly. (They were bred in retirement, and a supercolt is expected next February, says Jackson's widow, Barbara Banke.)

The son of a teacher and a secretary, Jackson paid his way through law school working as a longshoreman and police officer. He became a successful land-use litigator, bought 80 acres of Northern California fruit orchards in 1974, replanted it in grapes, and in 1982 produced his famous Chardonnay. "There was some animosity and jealousy," says Ullom, who was hired on as winemaker (and later wine master) for Kendall-Jackson and the Jackson Family wines in 1993. "It's unfair, what he did, hitting the nail on the head, becoming an overnight success."

Jackson bought up struggling wineries and turned their operations around. His particular skill was marketing: getting restaurants to sell his wines by the glass, which spreads the word rapidly; making labels attractive; setting prices to entice wine buyers. "He micromanaged but macromanaged as well," Ullom says. "He got up early. He'd have the world figured out by 9 a.m. And then he'd call meetings. If you didn't know your stuff, oh, my. He was like an attorney asking questions he knew the answer to."

After the millennium, Jackson tried retiring—repeatedly, says Banke, who chairs the company's board: "I told him, 'Enjoy travel. Enjoy the horses.' But every time we'd travel, he'd try to make a business. We'd go to Tahiti, and he'd think about growing vanilla [an idea he dropped]. We had good managers. You've got to give them room. I encouraged him to do that. That's why he got into horses."

At a memorial, 800 friends gathered, each raising a glass of Vintner's Reserve to Jackson, Ullom says. "His favorite wine."