Family #147 in the 1775 Grimm census.
Family #103 in the 1798 Grimm census.
Juliana Koch was the wife of Georg Koch; her last name at birth is unknown for now. She was born about 1734, probably in the Darmstadt area of what is now Germany. Juliana married her husband prior to the couple immigrating from Germany to Russia. In the Kulberg Reports, her husband is listed as a Lutheran farmer from Darmstadt. They immigrated to Russia with travel document number 4061.  The couple departed from Luebeck on the Pink Slon and arrived on 18 June 1766.  A Pink was a small, flat-bottomed ship with a narrow stern, typically square rigged and used to sail short distances and/or in shallow waters.  The Slon on this journey was commanded by Lt. Sergey Panov. 
The couple is listed in the 1767 Grimm census along with a one-year-old son Johann Adam. Their son must have been born in St. Petersburg or Oranienbaum, Russia shortly after their arrival in Russia. The village of Grimm was settled in July of 1767, so we can estimate their son's birth month as around July of 1766, after they arrived in Russia, but before they arrived in Grimm.
1767 Grimm Census 
At the time of the 1775 census, the couple had two children:
Not only is the name of his son different from the name of the son listed in the 1767 census, but their birth years are off by 3 years. This most likely signifies that the eldest son, Johann Adam, passed away before 1775.
There is also a discrepancy with Juliana's age in the 1775 census, where she was listed as being 9 years younger than her husband; in the 1767 census, she was listed as only 1 year younger. Unfortunately her age is not listed in the 1798 census, so a comparison can't be done. Her last name at birth is also not listed in the 1798 census, so it will be difficult to confirm through a German birth or marriage record, which would likely also confirm her birth year.
1775 Grimm Census 
Juliana Koch is listed as a widow in 1798, indicating that her husband had passed away between 1775 and 1798. She was living with their son Johannes and his family at the time of the 1798 census.
1798 Grimm Census 
Juliana Koch was almost certainly deceased by 1834. Had she survived she would have been 100 years old.
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