Mmm.. I imagine it was ported to Mac about two days after they converted to a Linux based OS. If there was a Windows port that long ago, I never heard of it.. but it's not impossible.
We even still have the installers available for those early versions at https://sourceforge.net/projects/wesnoth/files/wesnoth-1.0/
No guarantee they still work with modern versions of Windows though, of course.