Where does “stiftelse” come from?

stiftelse (Norwegian Nynorsk) comes from Norwegian Nynorsk stifte, from Middle Low German stiften.

stiftelse (Norwegian Nynorsk): a foundation

Definitions

Step	Language	Word	Meaning
1	Norwegian Nynorsk	stifte	to nail, tack, staple, pin; to establish, found
2	Middle Low German	stiften	—

stiftelse — Etymology, Origin & Word History | Etymology Explorer