Wilhelm Peterson-Berger was a man of his time
Peterson-Berger took serious interest in the swedish indigenous people, the sami. Something which he shared with his friend and painter Johan and brother Karl Tirén. The three of them made numerous mountain hikes together.
Wilhelm of course was a man of his time and having studied in Germany, strongly influenced by nationalism and romanticism. But as keen as he was about german culture generally and Nietzsche and Wagner in particular – this should not be confused with darker forces progressing and fuelling the coming nazism. In fact Wilhelm had a strongly negative attitude towards these influences. You can sense the influences of his keen interest in Beethoven and Wagner in Wilhelms music, possibly with Grieg coming in as third.