It’s widely believed that Sonoma’s first winemaker may have been Gen. Mariano Vallejo, who planted grapes in the Valley and worked closely with Agostin Haraszthy at what became Buena Vista Winery.

But local historian Peter Meyerhof will present a different theory at the Sonoma Valley Wine History Weekend, a two-day free series of events to be held in late July at both Buena Vista and the Depot Park Museum. Meyerhof will describe his original research, which revealed the name of the first winemaker at what became Buena Vista Winery.

This mystery winemaker was a Native American, believes Meyerhof, who had been taught to make wine by the Franciscan Fathers of the Sonoma Mission.

It’s a tantalizing story, and at 11 a.m. on Saturday, July 28, Meyerhof will present his theory at the Wine Museum on the third floor of the Champagne Cellars at Buena Vista Winery. It will be followed at noon by the unveiling of a new exhibit at Buena Vista Winery, describing this first winemaker, along with other artifacts and interpretive materials.

The Saturday Wine History Weekend program continues at 4 p.m. at Buena Vista Winery with the free, inaugural performance of a new play by George Webber, “An Uneasy Future: General Vallejo, the Count, and Joaquin Murietta in Sonoma.”

The play gives dramatic shape to the historical question: “What if General Vallejo and the Count helped hide the noted Californios bandit Joaquin Murietta?”

The following day, Sunday, the Sonoma Valley Wine History Weekend shifts to the Depot Park Museum, where at 11 a.m. a free lecture by Peter McGettigan, a direct descendent of Gen. Vallejo, will outline Vallejo’s own role in early Sonoma Valley winemaking.

Sonoma Wine History Weekend is presented by the Sonoma Valley Historical Society and Buena Vista Winery. For more information, contact the society at info@sonomavalleyhistoricalsociety.org, or Webber at thecount@buenavistawinery.com.