== total garbage == 

 Much of this page is absolute, total garbage.  For example, the whole set of sound and grammatical changes supposedly due to Celtic substratum influence is just junk.  It looks to me like a lot of original research done by an amateur linguist, looking at similarities between Celtic and Old French and therefore concluding that there must be a connection.  In reality, proving such connections is extremely hard, and most researchers in the field are doubtful of all such claims, especially for common sound changes, which many of these are.  When I have a bit more time I'm going to delete all the junk.  In any case a lot of info in Old French should go here instead.