Hi HL - We talked a while back about the french connection to the deboards. I have been trying to find this french connection to deboard and came up with this link through about.com. I thought I would look into it, but can't remember the name of the oldest deboard in US.

http://genealogy.about.com/gi/o.htm?zi=1/XJ/Ya&zTi=1&...

it lists a lot of people with surname deboard from france in the 17, 18th and 19th centuries. maybe this is helpful? Have you had any luck tracing further back than Pierre (was that the name of Isaac's father?)?