Greyshield is one of the Shield Islands in the Reach. The westernmost of the isles, it lies near the mouth of the river Mander. It is the site of Grimston, the seat of House Grimm.
Torgon Greyiron used Greyshield as a stronghold when he raided along the Mander.
The island of Greyshield is taken by Ser Harras Harlaw during the Battle of the Shield Islands. King Euron Greyjoy names Harras the new Lord of Greyshield.