Download-hearts-of-iron-4-field-marshal-edition-v1-9-1-online Official

If you’ve played newer versions, go to Documents/Paradox Interactive/Hearts of Iron IV and delete the shadercache folder to prevent crashes.

Click "Multiplayer" in the main menu. You can use the Steam "Invite Friend" feature or the Server Browser. If you’ve played newer versions, go to Documents/Paradox

In the "Beta Participation" dropdown, select . If you’ve played newer versions

Because v1.9.1 is a legacy version (modern versions are 1.14+), the "proper" way to get this specific build is to use the official version-rollback feature provided by Paradox Interactive. Step 1: Purchase and Installation If you’ve played newer versions, go to Documents/Paradox

To play online with others on this specific version, everyone in the lobby must have the same "checksum" (the version code). Right-click in your Steam library. Select Properties > Betas .