I have found a marriage record for Clara ASHFORTH 1895-1932 and Henry James WILLIAMSON 1894-1965. The marriage took place at Sheffield, Yorkshire, England in the June quarter of 1919.
I have also found a likely date of birth for a Henry James WILLIAMSON 1894-1965 in the June quarter of 1892.
I now need to obtain the certificate for this marriage, since this may hold some clues to whether or not Henry James WILLIAMSON 1894-1965 was born in England or New Zealand. I have added this to my task list.