Even if your entire family came from Norway it actually wouldn’t be that surprising that you’d get some DNA from other cultures popping up in there somewhere. The Viking Age, which spanned several hundred years, was pretty wild. The Vikings developed a type of boat that could sail the open ocean, but still had a shallow enough draft that it could navigate most of the major networks of Europe, and which was light enough that they could be carried overland from one river to another. It was an absolutely devastating technology for the time. They could often sail up a river, sack an entire city, and be gone before the surrounding area was able to raise an army to fight them off. As you can probably imagine the Vikings got all over the damned place. They got all the way to North America to the west, and pushed into Asia and founded Russia to the east. Some sold their mercenary services to the Byzantine Emperor in Constantinople and served in his Varangian Guard. They got around Europe so much and sacked so many European cities so often that at one point Europe straight up completely ran out of silver.

The Viking Age also overlapped with the Muslim expansion throughout the Mediterranean coast of Europe and North Africa. The Muslim conquest of the Iberian region of Spain, and the famous Viking raid on Lindisfarne in England only happened about 70 years apart. So the Vikings were also bumping into them as well. Most people have this idea of the Middle Ages where everyone pretty much stayed put, and nobody traveled more than 20 miles from where they were born. And while that was probably true enough for some people, lots other people moved around a ton, and there was actually quite a bit of cultural cross-pollination and trade. It’s not hard to imagine that somewhere in all of that one of your Scandiwegian ancestors might have gotten a piece of some Spanish hotness.

Also, when the Vikings went raiding, they didn’t just take silver, they also took slaves and brought many of them back to Scandinavia. And sometimes they had sex with those slaves. So there’s also that possibility.