Hmm, it looks ethnically "barbarian" (Celtic, Germanic, whatever) with the light skin and red/brown moustache... It's also well-armoured, and I don't think tribal cultures had access to such advanced weaponry (forgive me if I'm stereotyping), so, in a wild stab in the dark, I'm going to say it's a Gallic/Iberian mercenary supplied with Carthaganian weapons. (So it would be on Carthage's faction unit list, or available for recruitment in Iberia/Southern Gaul).
Barbarian isn't an ethnicity.
In addition, Gauls weren't really tribal at this point. And non Greek and Latin peoples made some of the best weapons and armor, which was often copied by their neighbours. Celts had great armor and weapons, many of which was copied by Rome. Celts invented chain mail, and many other typical types of armor we think of as Roman. Steppe peoples had some pretty ornate stuff as well, as did other less "civilized" peoples.