How can i change the resolution on Mount & Blade Warband (Linux version)?
There is no ingame option. I tried to set diplay_width and display_height to 2560 and 1080 inside the file called rgl_config.txt but nothing changed inside the game.
Any idea?

mbw_config_linux offers this option. You will have to "chmod +x" it first.

edit: apparently the setting is reverted to desktop resolution if windowed mode is not selected. Forget I said anything. The config program just modifies the settings you tried to modify as well.

Yes, setting on windowed mode did the trick. Too bad the max resolution supported seems to be 1920x1080. Still better then nothing.