Château Mouton Rothschild winemaker Lucien Sionneau and Robert Mondavi’s son Timothy made the partnership’s first vintage at the Robert Mondavi Winery in 1979. The following year the partners officially announced their joint venture. n 1981 a single case of the joint venture wine sold for $24,000 at the first Napa Valley Wine Auction – the highest price ever paid for a California wine. In 1982 Robert Mondavi and Baron Philippe de Rothschild began label design. The partners agreed to choose a name of Latin origin for the joint venture, allowing for easy recognition in both English and French. Baron Philippe announced his choice, “Opus,” a musical expression denoting the first masterwork of a composer. Two days later he proposed an additional word: “Opus One”.he 1979 and 1980 vintages were simultaneously unveiled in 1984 as Opus One’s first release. Opus One then became known as America’s first ultra-premium wine.

By far the most famous appellation in California is the Napa Valley. Encompassing virtually all of Napa County as well as 14 distinct AVAs (American Viticultural Area), this extensive valley system, is home to the cradle of California’s viticultural history. Napa Valley opens to the south where the climate is shaped by the maritime influences of the great San Pablo Bay. This regular influx of cool, damp air creates a meso-climate that is significantly different from that of the Northern reaches of the valley where the day’s heat can remain trapped and accumulates over the course of the summer growing season.The other great influences on the climate of the valley are the mountains that frame its contours. With the Mayacamas Range separating Napa from Sonoma on the west and the Vaca range defining the valley’s eastern boundary there are many varied exposures, elevations, and soils here that have been deemed worthy of special attention.