The Dettenhamer family owned an orchard business in San Jose, California. The collection is a compilation of their correspondence, immigration papers, family photographs, and business ledgers, some in German.

The Dettenhamer family consisted of Joseph and Ella Dettenhamer and their daughter Ella Marie. Joseph was a German immigrant who came to the United States in 1904 via New York City. Ella was previously known as Gisela Banovitz, but changed her name to Ella prior to meeting Joseph. She was a Hungarian immigrant who moved to the United States with her family in 1907. They met in San Francisco while working at the same residence, married in 1910, and eventually settled in San Jose, California, where they began their own orchard business on their property at 105 Bascom Avenue. They officially attained their citizenship in 1937. Joseph’s brother, Frank Dettenhamer, also immigrated to the United States and lived in San Francisco. The brothers wrote to each other regularly and on occasion Frank would help with the fruit harvests in San Jose. Ella Marie was born in 1914 and attended Burbank school, and eventually Notre Dame High School. After she graduated in 1932 she became one of the first employees at Moffett Field, where she worked as a secretary in the supply department. Ella Marie never married and lived at the family home taking care of her parents and uncle until their deaths. Ella Marie lived on the property until she sold it in 1991 to a developer who built medical offices. Ella Marie died in 2007. The Dettenhamer family kept notes and diaries about everything in their lives. Joseph saved materials relating to the orchard business, and the women would keep diaries and take pictures of their property and garden. The family also kept scrapbooks and photo albums of their life and family.

18 linear feet, 17 boxes, including approximately 70 photographs, 4 scrapbooks, and 4 photograph albums

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Collection is open to the public for research by appointment with the Curator of Library and Archives.