The name Grímnir indicates night, and masked;
gríma means night, and also a mask.

We shall understand names in Icelandic. That gives insight.

Edda poem Grímnismál, interpreted by the Icelander Einar Pálsson as the zodiac – funnily irritated the (–jealous–) Icelandic scholars to the extent that they refused to have him give a lecture in “their” university.
Haughtily uttered: “what could an actor in the west-end of town know about “their” subject of research”.

Einar discovered a lot more, both in Eddas and Sagas, to the even greater annoyance of the scholars, who saw not what Einar saw.