John Mudd is a sellsword in service to the Golden Company. His rank is serjeant.
He is a Westerosi exile. He may or not be of House Mudd, as in the free companies a man can call himself whatever he chooses. He may be related to another sellsword in the company, Lorimas Mudd.
John may have beeen present during Jon Connington’s rendezvous with the Golden Company three miles south of Volon Therys, as Jon Connington notices that a Mudd is present during the meeting.
Like the rest of the company, swears his allegiance to Aegon Targaryen before they invade Westeros.