Hello,
After long searches in French "etat civil" it appears that the ONLY Louis Dihars born in France around 1820 (+- 10 years) was Louis Dihars born March 21 1819 in Minzac (Dordogne), a little village situated about 30 km from Libourne.
He may be the one we are searching …
In his profile's media folder I've uploaded a screen shot of his birth certificate…
An other option is the John Dunmore thesis:
The French and the Maori - John Dunmore - 1992 - Page 128
https://books.google.fr/books?id=L2njAAAAMAAJ&q=Jean+Duhard......
"It seems likely that his real name was Jean Duhard, that he was born in Libourne (Gironde) in 1823, and that in New Zealand, like a number of other French people, he changed his name to start his new life with a new identity"
But as the ONLY Jean Duhard born in Libourne in 1823 (within a 10 years range), married in the same town in 1848 and then have children..
(I do have original sources)
With all my respect to the John Dunmore works, his hypothesis seems far to be right … How the same person can marry and have children in France, and have an attested life in New Zealand at the same time ? Even with the help of Star Trek Voyager's Transporter it may be a complicated situation … :-)
May I edit Louis's profile consequently ?