Napa Valley wine pioneer Peter Mondavi, Sr., has died at the age of 101.

Mondavi's family owns the Charles Krug Winery.

In 1943 Mondavi's parents bought the Charles Krug Winery, which was founded by Prussian emigrant Charles Krug in 1861, making it the oldest winery in Napa Valley.

Mondavi became CEO when his mother died in 1976. He acquired 800 acres to expand his vineyard on former dairy land. His winery became the first to import French oak barrels for aging, and he was among the first to plant pinot noir and chardonnay grapes in the region.

Mondavi helped change the reputation of Napa Valley into one of the world's leading wine making regions.

Related: Wine in a can, a keg, a carton...and it's not bad

His family said Mondavi claimed that his proudest accomplishment was "never losing control of our family winery," in the midst of many corporate buyouts that swept Napa Valley.

"If I could, I would tell my father: I did the best I could during the difficult years," he said. "I was determined and we held on."

He died Feb. 20 at his California estate. The winery is run today by his sons Marc and Peter Jr.

Correction: An earlier version of this article incorrectly stated that Charles Krug Winery had been known for lower-quality wines.