Jacob Rosenberg was born in 1834 in Fordon, Prussia. At the age of fifteen, Rosenberg trained to be a tailor and found work in cities and towns throughout Prussia. After immigrating to the United States through New York, he travelled to San Francisco by steamer in 1859 and then travelled inland to La Porte, then in Sierra County, where he worked as a peddler. He married Henrietta Rosenbaum in 1868. The couple would have six children: Sippa, David, Sarah, Ella, Samuel, and Josephine. In 1871, Jacob and his brother Julius (who has come to La Porte as well) started the firm Rosenberg and Brother.
The collection consists of genealogical information, a small amount of correspondence, Jacob Rosenberg's journal and notebook (which includes his memoir of his childhood and his experiences leaving Prussia and then settling and working in Northern California), handwritten prayer books Jacob Rosenberg made for two of his daughters, a citizenship certificate for Bernhard Wolff (Sippa Rosenberg's husband), and photographs. Among the photographs are family snapshots and portraits and 27 photographs of San Francisco in the aftermath of the 1906 earthquake and fire. Oversize items include a ketubah for Jacob Rosenberg and Henrietta Rosenbaum from San Francisco's Congregation Sherith Israel (1868), a marriage certificate from the City and County of San Francisco for David Hearsh and Ella Rosenberg (Feb. 25, 1910), a marriage certificate for Sippa Rosenberg and Bernhard Wolff (1901), and Josephine Rosenberg's 1903 diplom