The etymology of "Rockoff"

We were told that our great-grandfather's, Elias Rockoff's, last name was originally pronounced "Rakeoff" (not sure of the spelling) and it was changed by US Immigration officials. He was already in the United States in 1913, when my grandmother Bessie Rockoff was born in St. Louis, MO. I've been told alternately that he was from Russia or from Latvia, but I don't have documents to specify which.

@ Elias Rockoff:
Cousins...I have in my keeping the legal document for name change filed in Chicago January 3rd, 1921. The change was from Rakoff to Rockoff. This petition for name change was filed by Elias, Louis, and Isaac Rakoff. I also have my Granfather Elias Rockoff's ticket for passage on the Hamburg-American passage ( he came on the Patria) on April 26, 1896. The passanger list shows him as Rakove. Although some of the children, Louis most notably, came from Slutz, the family also resided in Rakovie, which is south east of Minsk. Sometimes this was Poland, sometimes Belarus. I am not real handy on Geni, but would love to get more posted. Let's share what we have!
Celeste Rockoff Mushet

So... instead of a patronymic (what I'd normally expect with an "-off" or a "-vitch" suffix), Rockoff derives from a "byname" (a second name associating a person with a place or a profession)? (Rockoff << Rakoff << Rakove << [from Rakovie)

Fascinating!
Did Sam & Elias Come by Their surnames the same way?

Todd, I am not familiar enough with your line to know, however...
Jewish people in the shetls did not have last names as such, and often took the
name of the town as they immigrated. The name "Samuel" is very common in
my family, including "Schlomo". Using the sites posted from Jewish Gen one can look at the Jewish school records and find Rockoffs there, but the cemetary lists no Rockoff
but does show "Samuel" as a surname. Indeed my ggtandfather Julius Schlomo
Rockoff could have been Julius Samuel from Rakovy or Rakowvie. Maybe another"cousin" has more information!?

"Julius Samuel from Rakovy or Rakowvie" would *almost* seem to follow the normal naming patterns. The "-vitch" and "-vna" name endings convert a name to a patronymic (indicator of the father's given name), just as "ben xxxx" and "bat xxx" do in Hebrew. (Other naming traditions use the father's name unaltered as a middle name, serving the same function.) In classic Russian literature, characters are commonly addressed as "given name + patronymic"; adding a byname -- especially the name of a small town -- would go a long way to remove any ambiguity between multiple persons with the same first name, whose fathers had the same first name.

As an aside, I find that even today, my friends and I often use bynames ("John from X" and "James from Y") rather than surnames in casual discussion, putting the third party in the context of how the listener knows him or her, or how all parties are socially related.

Thanks for these insights and suggestions.

Sam Rockoff was reportedly provided the surname at Ellis Island by a cleark who could not pronounce/parse his surname. That, along with the likelihood that he didn't go to school, renders unlikely his appearing in school records as Sam (or variant) Rockoff.

Does it work that Sam Rockoff, who we believe came to the U.S. from in/near Vilnius, Lithuania, might be from a village called Rakovy, and that's where the clerk at Ellis Island made up "Rockoff"?

Yes, it is all in the same general area, I will try to get a map posted for you. I have to get my sweet huband to do it, I am not to knowledgeable about this computer stuff....