I got Vassal to work on my Chromebook, its an Acer Chromebook 315. This method is not point and click, so you’ll need to be happy to use the Linux text terminal. Here are the steps I took:
Enable Linux on the Chromebook in the settings. This took a while on my machine. A folder for Linux files will appear in the folders section.
Open up the Linux terminal on the apps, by typing ‘terminal’.
In the terminal, at the prompt, do an update to the Linux system,
$ sudo apt-get update
Download the Java files,
$ sudo apt-get install default-jre
Check that Java is installed,
$ java -version
This will display the version of Java, and which was 11 at time of this post.
Download the Linux Vassal .tar.bz2 file , then ‘unpack’ it ( the ‘filename’ is the current name and version of Vassal),
$ tar -xvjf filename.tar.bz2
This will create a folder of the unpacked (unzipped) Vassal files, in the Linux folder. Show the folder in the terminal,
$ ls
For me the folder was called VASSAL-3.4.12
Change to this folder,
$ cd VASSAL-3.4.12
Download your Vassal games to this folder.
In this Vassal folder run Vassal by,
$ sh VASSAL.sh