Chadbourns
(no "e" on end), in most all cases in the U.S., descend from the same
1634 immigrant, William, who used both spellings.
The
book on the Chadbourne Family (1994) uses the name "Chadbourn" where it
is spelled that way by most descendants living today.
Those
who called themselves "Chadbourn" or used both spellings, but most of
whose descendants use "Chadbourne" are listed in this book with the trailing
"e".
Typically an electronic search for Chadbourn will find it
with or without the "e". In some cases one can search with soundex
code C316 or can use wildcard search characters such as the
* and ? in "Chadb*rn?" which may find all the above.
The
index of our 1994 book in print combines all spellings of Chadbourn(e)
and Chadburn, so don't be concerned about surname spelling when searching
the index of our printed book index - though you may have to take more
care with the CD edition tentatively to use the Folio search engine.
Chadburn in many cases indicates descent from the same man, 1634
immigrant William, especially those Chadburns who can be traced back to
Maine, Vermont, or Canada's Province of Quebec.