Listed in the 1850 Census for Bates Co., MO, living in District No. 6, dwelling #258, as John Blackburn, age 39, a farmer born in Kentucky. Enumerated with Nancy (a. 37, bp. OH), Samuel (a. 18, bp. OH, a laborer), David (a. 18, bp OH), Donushia[?] (a. 13, male, bp. OH), and Lavinia (a. 12, female, bp. OH). Henry Beaver's family is listed as living in dwelling #255.

His family is believed to have been a member of the 1853 Hagans-Cockrill wagon train. If indeed they did arrive in Sonoma County during that time, they left before the 1860 Census. Attempts to find them in other California counties in 1860 have so far not been successful.

According to short biography on "Nancy Beaver Blackburn" in Jeanne Miller's papers, he is presumably of the family of the first wife of James Anderson Cockrill (II). Considering that his middle name is Samuel, this is no doubt a correct assumption, but how he is connected to Samuel Blackburn is not known at this time.