Trefethen Vineyards was established in 1886 as Eshcol, a biblical word for “lush cluster of grapes.” Following retirement from a successful career with Kaiser Industries, Eugene Trefethen along with his wife Katie purchased Eshcol in 1968 along with six adjoining properties to create Trefethen Vineyards. At that time, replanting of the vineyards and restoration of the historic winery building began. The Trefethens' restoration efforts were recognized in 1988 by the Department of the Interior, which placed the winery on the National Register of Historic Places as the only 19th-century, wooden, gravity-flow winery surviving in Napa County. The winery is also known for an extensive garden established by Katie. It has been featured in many publications and has been a destination for many gardening enthusiasts since it was created.
Eugene Trefethen died in 1996 and Katie Trefethen died in 2007.