In the latter 1990's ESRI released ArcView 2.0 and made version 1.0 available for free download. It is no longer available on ESRI's site but can still be found here and there. Namely:
ftp://download1.geocomm.com/sd2/ARCVIEW10.ZIP
It requires Windows 3.1 (or Windows For Workgroups 3.11).
Other references: