Given the various Census entries for John May who is recorded as from Wiltshire, Somerset, Coatham, and West Dean, very difficult to be sure , however here is a candidate which would put him in the area of Wiltshire/Somerset border in a quarrying village of Corsham which might explain him turning up in the Forest of Dean.
John's occupation in 1871 is Clay Grinder.
JOHN MAY
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Event(s):
Birth:
Christening: 18 JAN 1835 Corsham, Wiltshire, England
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Parents:
Father: WILLIAM MAY
Mother: SARAH
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Messages:
Extracted birth or christening record for the locality listed in the record.
The source records are usually arranged chronologically by the birth or christening date.
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Source Information:
Batch No.: Dates: Source Call No.: Type: Printout Call No.: Type:
C153432 1833 - 1885 1279378 Film NONE
Sheet: 00
This John has brothers Samuel and David ( at least)