I'm not sure if you have been successful in finding info regarding Bluford (also spelled Blewford) Lewing.I descend from one of Bluford's 21 children (Luallen G. Lewing - my great great grandfather)and have somewhat limited info but am willing to share.Bluford was married to Miami Virginia Dupre (also spelled Dewpree and Dupree), daughter of LeFrey and Elizabeth Dupre.Bluford's mother's name was Elizabeth Carnes.Although, Carnes may have been a second marriage name rather than maiden name.
Bluford is presumed to have been born in the US on the Mississippi River.I have not been able to substantiate this so I regard it only as legend (which as you may know is something the Lewings are full of).
Miami Virginia Dupre, his wife, was born in France according to a census record.
As far as general information relating to the origins of the Lewing name, the earliest instance of the name Lewing (spelled Lewing) that I have found is the late 1500s in England.Appearing concurrently is the name Lewin (no G at the end) throughout the British Isles.I do not believe this is the origin of the surname.
Sounding like Lewin is a Dutch name Van Leeuwen.The "Van" part of the Dutch version of the name is like saying "of" or "from" in English.The last name Van Leeuwen (meaning "of Leeuwen") appears in the Netherlands in the late 1400s.I suspect that Lewin is an anglicized version of Van Leeuwen. It would be my guess that this is the beginning of the surname.Leeuwen (which translates to "of the lion") is a place near the village of Tiel in the province of Gelderland, Netherlands.
There is at least one line of Lewings who migrated into what was then Prussia (now primarily Germany) and descendents from that line continued further into Russia.
Hope this gives you a little food for thought.Take care, Cheryl