Public Domain and Royalty-Free Video Clips
The Prelinger Archives
The Prelinger Archive is a subset of the Internet Archive. Prelinger Archives was founded in 1983 by Rick Prelinger in New York City. Jt is a collection of over 60,000 “ephemeral” (advertising, educational, industrial, and amateur) films. A portion of these are available online. The Prelinger archive has it’s own terms of use and all films are listed as “public domain” under the Creative Commons license. The site notes that while the films themselves are public domain, all elements of the films may not be. This is a great collection to locate pieces of footage that depict life in the early and mid 20th century.
https://archive.org/details/prelinger
Wikimedia Commons
https://commons.wikimedia.org/wiki/Category:Videos
Pixabay.com
Pixabay has over 1.3 million images and videos. All contents are released under Creative Commons CC0, which makes them safe to use without asking for permission or giving credit to the artist – even for commercial purposes.
Pond 5 Public Domain Project
Pond 5 is a major supplier of media clips and a good place to sell your own stock footage, images, music and sound effects. But, in addition to the media they have for sale, they have established a section of public domain media that is available for download at no cost. You’ll have to set up a free account to download the clips, but it’s worth the effort. Most of the clips and stills appear to be European and there are a lot of WWII vintage items.