Berrigan is a retired Ranger who lost one of his legs in battle against the Skandians before they were allies. After this, he mainly earns his living as a jongleur.
History
Berrigan sometimes works undercover for the Ranger Corps, something which Will eventually guesses in The Sorcerer in the North. In the fifth book, he teaches Will how to be a jongleur with his mandola in order to have cover in Macindaw, and travels with him part of the way. Will later uses the skills Berrigan taught him while he is in Norgate Fief.
He plays a gitarra, the equivalent of a guitar, and is said to be very good at it; he also has a fine singing voice, often entertaining the Rangers at Gatherings with Will occasionally accompanying him on his mandola. His jongleur cloak is patterned similarly to a ranger camouflage cloak, though it is more brightly colored.
Halt, Crowley, Berrigan and several other Rangers were mentioned to have been sent to destroy the first outbreak of the Outsiders in 631 C.E., driving the cult out of Araluen.
The Tournament at Gorlan
Berrigan is one of the minor characters who is one of the last twelve Rangers to be expelled from the Corps by Morgarath. He was stationed in Welson Fief before his dismissal and was to be taken by Willet, on charges of 'treasonous talk' for singing "Old King Artur, the Terrible Farter". He was the second Ranger to be recruited by Crowley and Halt, later he sent a pidgeon mail to Pritchard telling him about the situation which prompted the veteran to join up with the group.
He is also one of the twelve rangers that stop Morgarath in The Tournament at Gorlan, where he joined Crowley, Halt, Leander, Farrel, Samdash, Berwick, Jurgen, Lewin, Norris, Pritchard, and Egon. He was said to have created the Ranger Song "Cabin in the Trees".