I think the 19th century part of this, after the real life murder mystery, was fine, interesting, well-acted and very believable - although no one can of course know if this was what really happened. But the culprit and the motive were an original and not impossible suggestion. I also liked it a lot that they used real Norwegian actors who actually spoke Norwegian, in the scenes that should take place back in Norway. That, and also the fact that the Norwegians wore Norwegian clothes from the right time period and had with them some Norwegian furniture etc. to America, gave it an authentic feel.
I did not think that the cutting between modern times and the 19th century worked, though. There were too many people to keep apart, and especially towards the end the cuts became too short and too fast and it all became just muddled. I am not even sure I understood what happened on the sailboat in the modern times. It would have been a much better idea to do the 19th century murder mystery only, and flesh it out a little instead.
I did not think that the cutting between modern times and the 19th century worked, though. There were too many people to keep apart, and especially towards the end the cuts became too short and too fast and it all became just muddled. I am not even sure I understood what happened on the sailboat in the modern times. It would have been a much better idea to do the 19th century murder mystery only, and flesh it out a little instead.