In your environment - Gnome

Ubuntu / Debian

A Gnome session for xmonad is part of the distribution package, however it is out of date. You can use the gnome-session-xmonad PPA to get an updated version.

Other Distributions

If your distribution is running Gnome and X similar to Ubuntu then you will need an Xsession file, Gnome session file, and (if that is your init system) a systemd session configuration. The following file listings are from gnome-session-xmonad source.

Common Problems

Historical Versions of Ubuntu

The wiki has signifcant material on how to configure XMonad with Gnome for Ubuntu versions prior to 16.04 Xenial (LTS).