William Seavey, founder of Seavey Vineyard in St. Helena’s Conn Valley, died at his home on Sept. 21, following a long illness. He was 86.

Mr. Seavey had a notable career as a lawyer, educator and public servant before he and his late wife, Mary, began their lives as vintners. Now in its 26th harvest, the Seavey winery has distinguished itself among Napa Valley Cabernets for its wines’ exceptional ability to age and rustic, restrained style.

The estate model, in which a winery grows all of its own grapes, is an increasingly endangered species in Napa Valley. Seavey Vineyard is a holdout from a bygone era. “Dad was very proud of always farming our own land with our own crew,” said his daughter Dorie Seavey, now the winery’s president. “He was a man of few words. He would raise his right hand and shake his finger and say, ‘I’ve never bought a grape in my life!'”

Born in Los Angeles in 1930, Mr. Seavey grew up in Coronado, near San Diego. He was an avid swimmer from a young age. As a child, he was a boy scout, and delivered newspapers on his bicycle; during World War II, he was a neighborhood messenger, going from house to house to warn of power outages. He attended Princeton University and Harvard Law School, where he met Mary, then an undergraduate at Radcliffe College.

His pre-wine career included stints as the mayor of Coronado and the assistant U.S. attorney there; a doctoral degree (and successful ascent of Mont Blanc) from the University of Geneva, in Switzerland; a lectureship at Mills College in Oakland; an internationally focused law career in San Francisco; and the founding directorship of the French-American Chamber of Commerce.

In 1979, the Seaveys purchased the 200-acre property at the base of Howell Mountain. The seller? His daughter Dorie’s former geometry teacher, who had hosted Dorie and classmates for weekends at the ranch years before. The property has a long, rich history, originally as the Franco-Swiss Wine Company, which operated as a winery, dairy and distillery; then, during Prohibition, as a cattle ranch.

The promise of the site was clear early on. An 1882 article in the St. Helena Star notes that the Franco-Swiss “vineyards are models of good care and excellent cultivation.” It goes on: “The quality of the grapes produced by it is evidenced by the wines now in the cellar, one of which — a Zinfandel Claret — we have rarely seen equaled.”

The Seaveys set to work replanting the vineyard, whose vines total 40 acres, and produced their first vintage of wine in 1990. The original 1881 dairy barn was retrofitted to serve as the winery. Gary Galleron was initially the winemaker; Philippe Melka, now a very well-known consultant, was its winemaker from 1995 to 2000, at which point he switched to a consultant role. (Jim Duane holds the role today.) Together, Melka and Mr. Seavey honed the distinctive style of the estate’s wines: structured, rugged and elegant, showcasing the quintessentially chewy tannins of Howell Mountain.

“They never put any emphasis on marketing,” Dorie said. “They just hoped that people would come discover the wines.” And they did — winning critical acclaim (Robert Parker once called Seavey “one of the great, unheralded, under-the-radar terroirs in all of Napa Valley”), if quietly.

Mr. Seavey put a good deal of the property into conservation easements, ensuring that it would always remain undeveloped. He chose to farm conscientiously. Cattle have long roamed the vineyards. A lover of aged, Bordeaux-style wines, Mr. Seavey held back one-quarter of the winery’s 4,000-case production every year in order to keep a substantial wine library. Today, Seavey is known for its frequent releases of well-aged wines.

“Dad was very proud of keeping things really simple, and he thought that our way of winemaking — very gentle, patient, showing a lot of restraint — was the best way to handle the grapes that our property produces,” Dorie said.

His health was in decline for over six months before he died of lung complications. Mr. Seavey maintained his characteristic dignity through the end. “He was of that generation,” Dorie said, “stoic, never complaining, hanging on to each day.”

His death is preceded by his wife Mary’s in 2008. He is survived by his children Dorie, Art, Will, Fred and Charley; granddaughters Sarah and Annie Jefferson; and grandsons Jason and Cole Seavey.

In lieu of flowers, the family suggests donations to the Land Trust of Napa County. Details about a memorial service will be shared at a later date.

Seavey Vineyard, 1310 Conn Valley Rd., St. Helena. 707-963-8339. www.seaveyvineyard.com Open for tastings, by appointment only, 10 a.m. to 4 p.m. daily.