Appleton has been given a contract until the end of the 2014/15 season and, according to Pompey, has won the job ahead of other outstanding candidates that did appear to include Clarets' boss Eddie Howe.
Having had to retire as a player prematurely in 2003, he joined the coaching staff at West Brom and became assistant to both Roberto Di Matteo and more recently Roy Hodgson. This will be his first management role other than a short spell in caretaker charge at the Hawthorns.