Here's some info I know

COPYRIGHT TERMS:
Unless a source is explicitedly stated, text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. Articles may be a remixes of various Wikipedia articles plus work by the website authors - original Wikipedia source can generally be accessed under the same name as the main title. This does not affect its Creative Commons attribution.

Maps upon this website are in the public domain because they are mechanical scans of public domain originals, or - from the available evidence - are so similar to such a scan or photocopy that no copyright protection can be expected to arise. The originals themselves are in public domain for the following reason:

	Maps used are in the public domain* in the United States, and those countries with a copyright term of life of the author plus 100 years or less.*
This file has been identified as being free of known restrictions under copyright law, including all related and neighbouring rights.

This tag is designed for use where there may be a need to assert that any enhancements (eg brightness, contrast, colour-matching, sharpening) are in themselves insufficiently creative to generate a new copyright. It can be used where it is unknown whether any enhancements have been made, as well as when the enhancements are clear but insufficient. For usage, see Commons:When to use the PD-scan tag.