The Corsairs of Umbar are type of infantry for Mordor, serving either as Swordsmen or as fire-bomb throwers. They also are allies of the Goblins (and of Mordor) who are summonable from captured Inns.
In The Battle for Middle-earth II, they cannot be upgraded with Forged Blades. In The Rise of the Witch-king, they can.
See Corsairs of Umbar at One Wiki to Rule Them All.
Recruited from: Tavern; from the Haradrim Palace in RotWK
Command Points taken: 60