That green cornice-topped building on Napa’s Main Street that houses the Opera House offices? In the 1940s, local Jews used to meet on the second floor, just above Lazarus Auto Supply, to welcome Shabbat.

That elegant Victorian mansion with the Queen Anne turrets which today headquarters St. Clement Vineyards in St. Helena? Jewish winemaker Fritz Rosenbaum built it in 1878 for his family (including daughter, Bertie, who was almost murdered a few years later by a jealous suitor).

These are just a few of the fun facts found in “Napa Valley’s Jewish Heritage,” a new photo-illustrated volume in Arcadia Publishing’s popular Images of America series.

Jules E. Straus’ dry goods store (left) at 123 Main St. served Napa’s growing population in the wake of the Gold Rush.

Napa retirees Donna Mendelsohn and Henry Michalski — both principals of the Jewish Historical Society of Napa Valley — co-wrote the newly released book. The two met as members of Napa’s Congregation Beth Shalom, and in addition to a shared love of Judaism, both had a curiosity about Napa Valley’s Jewish history.

It turned out that much of the history had yet to be told. Recalls Mendelsohn, “A friend of mine once told me that when she had gone to the Napa Valley Historical Society and asked about early Jewish pioneers, she was told there were no Jews [there] in the 1800s and early 1900s.”

So not true.

The 128-page book packs in a lot of history, much of it told though archival photographs the authors uncovered at local historical societies. They used those photos to retell a fascinating narrative about a place that once was not so upscale.

“Life was very difficult,” Mendelsohn says of Napa’s early days. “There were no roads, no hospitals, no services, no schools for the most part. You had to be a pioneer to be in this area. It was bucolic and beautiful but in a primitive way.”

She and Michalski learned that Jews flocked to Napa in the wake of the 1849 Gold Rush, opening dry goods stores and providing other necessities to the region’s growing population.

The authors discovered tales of enterprising, hard-working Jewish immigrants determined to make a life in the narrow valley. Many got in on Napa’s wine industry as it first developed.

“Since wine is really important in Jewish history, the majority of Jews who became involved in the industry did it for the great love of wine,” Mendelsohn notes.

Abe Lachman started making wines in the 1870s, building a business that became one of the state’s largest wine merchants.

By 1902, the California Wine Association, backed by Isaias Hellman and other Northern California Jewish financiers, controlled more than 50 wineries. Lachman’s nephew, Henry Lachman, ran the association and later acquired Greystone Cellars, now home to the Culinary Institute of America, a prominent landmark along Napa’s Highway 29.

Throughout Prohibition, Jew-ish vintners continued to produce what were called sacramental and medicinal wines.

During that same period, Mendelsohn notes, a national wave of nativism and anti-Semitism rolled over the region, even striking Napa. The Ku Klux Klan once marched in the valley. Though she found no evidence of violence, Mendelsohn says many Jews left Napa, only to return after the Depression.

But other Jews thrived. In 1906 immigrant Nathan Rothman started Rough Rider, a Napa garment business that thrived into the 1970s (it was the first manufacturer to put zippers in pants).

There were few synagogues in Napa until relatively late. Jews met in homes, social halls (such as the one above the auto supply shop) or at shuls as far away as Vallejo.

Members of the private Gentlemen’s Outing Club (right) got together for camping, boating and other outdoor pursuits.

In her research, Mendelsohn learned that a synagogue apparently existed in St. Helena back in the late 1800s, though documents revealed little. She located the building and took a tour. In the basement she found hooks in the ceiling, used to hang poultry for kosher slaughter.

As the story shifts to recent decades, Napa becomes home to a thriving Jewish community, anchored by Congregation Beth Shalom, which opened in 1953. The book profiles notable Napan Jews, from present-day winemakers to Leo Trepp, the German-born rabbi who fled Hitler in the 1930s and became Beth Shalom’s first spiritual leader.

As Mendelsohn points out, the narrative continues. Her synagogue is currently overseeing the acquisition of Napa Valley’s first Jewish cemetery, which will be located at St. Helena Cemetery.

And the last page of the book includes a photo of Dan Eisner, Beth Shalom’s education director, showing b’nai mitzvah children the Torah scroll. Those kids will continue the Napa Valley Jewish story well into the 21st century.

Now that she’s co-written the book on Napa’s Jewish history, how does she assess the experience?

“It was wonderful,” Mendelsohn says about her sleuthing. “I got very excited that we were providing something the community didn’t know about. Every time we found one clue, we found something else.”

Photos reprinted with permission from “Napa Valley’s Jewish Heritage,” by Henry Michalski and Donna Mendelsohn. Available from Arcadia Publishing at www.arcadiapublishing.com or by calling (888) 313-2665.

“Napa Valley’s Jewish Heritage,” by Donna Mendelsohn and Henry Michalski ($21.99, Arcadia Publishing, 128 pages)

Authors Donna Mendelsohn and Henry Michalski will appear at a reception and book-signing at 11 a.m. Aug. 19, at the Napa Valley Museum, 55 Presidents Circle, Yountville. Also 6:30 to 8:30 p.m. Sept. 6 at St. Helena Public Library, 1492 Library Lane, St. Helena. Information: (707) 251-9092.