On a whim I looked up the TV series, only to realise there's now a much newer adaptation as well. The one I was referring to is this one from 1971:
https://www.primevideo.com/detail/0QGEAKI5A10J71NPXAXEX4GSHS
Among the more internationally renowned actors in it you'll find Liv Ullman and Max von Zydow. There's a sequel - Nybyggerna ("The New Land", which is not a direct translation; the original title is better translated "The Settlers") - which I also remember as being good, but I haven't watched either since the 1980's.
But there's also this new adaptation from 2022 which I have not seen: