Jabbar is the official wise man of a tribe of D'regs met by Sam Vimes during the events of Jingo.
- Carrot: "He's their... well, he's like an official wise man."
- Vimes: "Oh, so he's not the one who tells them (i.e. the D'regs) to charge?"
- Carrot: "No, that's the leader. Whenever they have one."
- Vimes: "So perhaps Jabbar tells them when it's wise to charge?"
- Jabbar: "It's always wise to charge, offendi."
He is a bearded man, as befits a Son of the Desert in Klatch, and has a sly edge to him. He is a likeable fellow, although one who would cheerfully kill anybody whom he disliked or from a different tribe. He tries to test Vimes with such ordeals as eating a sheeps eyeball, but is impressed when Vimes won't fall for it.
He owns a camel called Evil Brother-in-law of a Jackal.
He takes Vimes to meet 71-hour Ahmed deep in the desert, and helps win the incipient war before it becomes one.
Jabbar is described - as are the D'regs themselves, despite their Northern-African-inspired name - to be very similar to the Afghan Mujahideen, where the the basic units of mujahideen organization and action reflected the highly segmented nature of Afghan society - i.e. they all fought each other under their warlords. In the face of foreign (in this case, Soviet) opposition, however, the main mujahideen parties allied themselves into a single political bloc whose uneasy alliance lasted as long as the war and then disintegrated. An Ogg-like alliance, as a matter of fact.
Also note that the "Gom Jabbar" was a fictional weapon from Frank Herbert's "Dune" saga, a poisoned needle beloved of assassins.