The deadlift is a compound lift, hitting primarily the hips (hamstrings and glutes). So, you'd be best to put this in a leg workout, namely lower pull.
However, deads also require effort from basically your whole body, especially in the back, core, and the rest of your legs. Deadlifts will work your whole back, not quite directly though since the back isn't really "constracting" but supporting the weight lifted. It'll supplement your other back/pull lifts. They also give the traps a heavy beating. Since starting Rack Pulls a few weeks back my traps have actually taken off.