The boat burials of Valsgärde, Sweden, might be slightly before the Viking Age. But you’ll see them mentioned a lot in various articles on this site. A recent study reveals that the warriors in these burials were resting on feather beds. Read more: Birgitta Berglund and Jørgen Rosvold, ‘Microscopic identification of feathers from 7th century boat burials at Valsgärde in Central Sweden: Specialized long-distance feather trade or local bird use?’ in: Journal of Archeaological Science: Reports (Volume 36, 2021).