The game failed to run at first throwing an error along the lines "Failed to create device for rendering..."

To fix I did a quick Google and found I needed to add an options.txt file to this location: ~/.steam/steam/steamapps/compatdata/1011390/pfx/drive_c/users/steamuser/My Documents/My Games/FieldOfGloryEmpires . In the options.txt file I had just three lines:

RezX 1920 RezY 1080 Fullscreen 0

After that the game booted up beautifully and I've been playing for about an hour now without a hitch.