Established in 1978, Opus One is a brand of premium California wine produced in Oakville. The brand was launched by Baron Philippe de Rothschild of the famous Rothschild family and owner of Chateau Mouton Rothschild, and Robert Mondavi - a world-renowned wine producer - and has skyrocketed into fame to become one of California's First-Growth wineries. First marketed under the name NapaMedoc - it was renamed Opus One in 1982. The winery is now co-owned by Rothschild and Constellation Brands, who purchased Robert Mondavi Winery in 2004 and negotiated a 50/50 venture with the Baron the following year. Opus One produces an estimated 25,000 cases annually and is cited as one of California's ultimate cult wines, offering primarily Bordeaux-style grape varieties. Under the watchful eye of wine master Michel Silacci, Opus One has reached worldwide acclaim, becoming the first ultra-premium California wine sold throughout France and internationally.