Bless the Library of Congress for making so much good stuff available. To quote from its website,
This page features items from the Library’s digital collections that are free to use and reuse. The Library believes that this content is either in the public domain, has no known copyright, or has been cleared by the copyright owner for public use. Each set of content is based on a theme and is first featured on the Library’s home page.
These sets are just a small sample of the Library’s digital collections that are free to use and reuse. The digital collections comprise millions of items including books, newspapers, manuscripts, prints and photos, maps, musical scores, films, sound recordings and more. Whenever possible, each collection has its own rights statement which should be consulted for guidance on use. Learn more about copyright and the Library’s collections.
I can’t add to that description, but will share some of the delights that appealed to me as I browsed the collections.
Japanese woodblock prints
Covers and Miscellaneous
Word of warning, you can spend many hours poking around the Library’s offerings. And what’s shown on the Free to Use and Reuse Sets is a small fraction of what’s available. The digital collections contain thousands of items, some more esoteric than others.