Only a few reach the skin
Of the twelve cranial nerves, the trigeminal carries almost the entire cutaneous supply of the face, divided into ophthalmic, maxillary and mandibular fields. The facial and vagus nerves contribute small auricular territories.
The cervical contribution
The posterior scalp and the angle of the mandible are cervical, not cranial — supplied by C2 and C3. This is the transition on which the occipital concept is built.