Download of VASSAL 3.6.19 was on the developer's website when we last checked. We cannot confirm if there is a free download of this software available. The common filenames for the program's installer are javaws.exe, VASSAL - 3.2.6.exe or VASSAL.exe etc.
VASSAL works fine with 32-bit and 64-bit versions of Windows XP/Vista/7/8/10/11. We recommend checking the downloaded files with any free antivirus. The most popular versions among the program users are 3.2 and 3.1. The program is categorized as Games. The actual developer of the free software is The Vassal Team.
From the developer:
Vassal is a game engine for building and playing online adaptations of board games and card games. The program can be used in order to play games in real time over the Internet or by email. The program also allows you to build your own game modules and play them online.
You may want to check out more software, such as Mount & Blade. or Discord Times, which might be related to VASSAL.