Born at Vechta Oldenburg Germany
Pioneer of California
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San Francisco Call, Volume 77, Number 81, March 1, 1895, pg 11, col 3: "Death of Pioneer. J.G. Ernest Janssen, and Oakland pioneer, died yesterday of heart trouble at 515 Eighth street, where he resided. He leaves a widow, two sons and five daughters. Deceased came to Oakland in 1856, where he went into the grocery business. Later he became connected with the wholesale grocery firm of Kruse Euler in San Francisco. Janssen was born November 7, 1830, in Oldenburg, Germany. He was a member of Oakland Lodge No. 118, I.O.O.F."
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San Francisco Call, March 3, 1895, pg 6, col 3: "JANSSEN— In Oakland, February 28, 1895, F. G. Ernst, beloved husband of Leontine Janssen, and father of Mrs. A. E. Pirrie. Mrs. Louise Lange, Mrs. H.J. Katzenbach and Leontine, Carl, Mina and Edward Janssen, a native of Oldenburg, Germany, aged 64 years 3 months and 21 days.
"Friends and acquaintances are respectfully invited to attend the funeral this day (Sunday), at 2 o'clock p.m., from Odd Fellows' Hall, corner Eleventh and Franklin streets, Oakland. Services under the auspices of Oakland Lodge No. 118, 1. O. O. F. Interment. Mountain View Cemetery."
Newspaper articles provied by Adriana. Jan 17, 2013
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"Ernst Janssen was indeed an immigrant from Germany. I'm a far relative of Ernst's brother: Peter Wilhelm Janssen. I wrote my masterthesis on this person.
Through letters I found out that Ernst was related to P.W. Janssen (1821-1903). Ernst brother also moved out of Germany and settled in Amsterdam, where he became incredibly rich and famous. Because of his finacial support to some railroad company in the US (through his grandson Jan de Goeyen) numerous places in the US still commermorate this person.
Nevertheless, Ernst Janssen went already to the US in 1848, in Coloma to be exact. He was hoping to gain a fortune with goldmining. So, Ernst Janssen was one of the first Germans who got struck by the famous 'gold-fever'.For more info you can contact me!"
Bio provided by Paul Holthuis [email protected]
April 8, 2013
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Frederick G. Ernst Janssen was a California '49er and for many years prominently engaged in the wholesale grocery business in San Francisco and a man of recognized influence and position in that, city.

He was born in Oldenberg, Germany, November 7, 1830, was reared and educated there, and as a youth of nineteen he set out to the United States, going around the Horn on the ship Talisman and reaching San Francisco September 12, 1849. He immediately went to the mines, but remained there only a short time. In San Francisco he set up in the retail grocery business, and when his store was burned he operated a wagon, selling his wares at the customer's door. He next engaged in the grocery business at Oakland at First and Broadway, and there again was visited by fire. His next store was at Sixth and Broadway. Selling this business he went to Europe. Having lived in America for several years, he could not accommodate himself to the restrictions of Germany, and soon left and arrived in San Francisco shortly after the earthquake of 1868. He became associated with the wholesale grocery firm of Kruse & Euler, and was in business until he finally retired. He was a charter member of the Odd Fellows Lodge at Oakland, and a member of the Society of California Pioneers.

In December, 1855, Mr. Janssen married Leontine C. L. Helmke. She was born in Germany, and she and her husband were married in San Francisco. Of their thirteen children five are now living: Antoinette, of Chicago, widow of William Pirrie; Leontine C. L., of Oakland; Mrs. Louise Bartels, who resides in San Francisco; Mina, wife of Fred Helmke, of Fort Seward, California; and Edward A., of San Francisco.

- "The San Francisco Bay Region, Vol. 3" by Bailey Millard; Published by The American Historical Society, Inc., 1924