The initial content was copied from http://web.archive.org/web/20210706230345/http://mingw-w64.org/doku.php which makes it CC-BY-SA-4.0
The logos of external projects are copied from their respective project websites.
The main logo (logo.svg) was created by Dave Gauer [email protected] and is licensed under CC-BY-SA-4.0: https://github.com/ratfactor/mingw-w64-logo