Unther

Unther, like its long-standing enemy, Mulhorand, was once a great empire, but now seems to be in decline. The magocratic country was ruled by the Northern Wizards from the capital of Messemprar, since the former capital of Unthalass is occupied by Mulhorandi forces.

The city of Shussel hosted a Shou Town (source)

Navy and seafaring
Vessels from Unther were named after sea creatures or sea-related myths.

AD&D Information
"The language of Unther is called Untheric. It belongs to the same language family as the language of Mulhorand, but it so greatly changed over the course of many centuries that there are now very few similarities between the two languages. The runes used by the Untheri are entirely different from those used by the Mulhorandi; these runes pre-date their migration from Raurin. Early Untheric writing consisted of syllabic hieroglyphs (runes that represent one syllable, as opposed to the hieroglyphs of Mulhorand, which represent one word) and seems to have had at least minor influence on the alphabet of Thorass (Old Common)."

Post-Spellplague
Like its neighbor Mulhorand, Unther was completely wiped out by the Spellplague. The Untherians and Mulhorandi armies in Unther were almost entirely erased, and a fragment of the dragonborn nation of Tymanchebar was transplanted from Abeir onto Unther. As of 1479 DR, these dragonborn have formed the realm of Tymanther, named in honor of their native realm and the realm that it destroyed.