TheAdmiral wrote:
All I know about my family is that on my Fathers side we were originally from Norway with the family moving to England in late 1800's / early 1900's. Surname now is Nelson but is thought to originally have been either Neilsen or Neilson or some other similar derivative
So Horatio is unlikely to be on my family tree - However there could well have been several Vikings!
If from Norway, most likely Nilsen or Nielsen.
Most Danish and Norwegian common last names come from the shift from traditional naming to having a family name.
Like; Olafr, son of Haraldr, from Tromsø would become Olafr Haraldrsson av Tromsø. That's the old ways of naming.
Not too long ago, (100-150 years afaik) some laws changed, for example due to the constitution (1849) and people adopted their current "Haraldrsson" as their family name, unless they had a sizeable estate or other reason to choose another name.
So it's likely that your ancestors were either named Nilsen, Nielsen or simply that the guy who migrated from Norway was called Nils or Niels, but in England was called Neil, so he anglofied it to Nelson.