This is my great grandfather's surname. He immigrated to the US from Spain around 1850. I'm pretty sure it's not a Spanish name, but his father, William Nels lived there and married my very Spanish great great grandmother. It's very puzzling how a Nels wound up in Spain.
It's our family name. My grandfather came from Holland in the early 1900's. I always thought that it was a dutch name. My mother just told me that our ancestors in Holland came from Sweden. Don't think I like that. I've always thought that I was all Dutch. All the other grandparents came from Holland around 1900.
I've never seen this in Sweden. I would guess it was used among early Swedish settlers in America. According to statistics there are only 26 Nels in Sweden, so I don't think this should be considered a Swedish name at all. [noted -ed]