During WW1 there were a lot of Belgian refugees in Barrow-in-Furness, which was in Lancashire at that time as Geoff-E has already indicated, rather than Cumberland. My guess is that M. Fraigneux was Belgian. This seems to be relatively common Belgian (Walloon) surname.
A quick check of the Belgian records shows that there was a Jean Baptiste Fraigneux who married at Liège, Belgium on 13 November 1897 (to a Mlle. Marie Gobert). However, without additional information it is impossible to determine one way or the other if this is the same M. J.B. Fraigneux who has surfaced in the course of your enquiry.
It may be possible to get a list of Belgian refugees living in the Barrow-in-Furness area from the County Archives office at Barrow. if so you might find some additional information about the M. Fraigneux you have come across. If you could get a list of refugees it might also indicate if there was a wife who was also a refugee in the area. The 1947 marriage certificate would, of course, state if the bridegroom was a bachelor, widower or divorced.
Good luck. I hope this helps a little.
