Lantan

Lantan is an island nation from the Forgotten Realms. It has been part of the setting since the original 1E Forgotten Realms Campaign Set, which is still the main source for a lot of info on it. It's home to Gnomes (which are basically described as Tinker Gnomes, but competent) and a smaller number of Humans of Lantanna ethnicity (described as “ivory” to “parchment” skin with copper-red hair and large green or black eyes). These people live on rock pinnacles atop lush jungles that are connected by bridges. They worship Gond as their state religion, to the near exclusion of other deities. It is ruled by the Ayrorch, 12 people who serve for life on the council and select their own replacements.

What’s actually interesting about the place is that, instead of how Gnome "inventors" normally go, they’re actually successful at invention, totally ignoring the Medieval Stasis that infests the rest of the setting, possessing roughly Renaissance level of technology, with them having pistols (standard equipment for those hailing from there), early printing presses, coaches (not carriages, but their far more weight efficient successor), replaceable parts, and far more science fiction level devices. They have printing presses, but while 1E describes them as having violently stolen it from Halruaa, 3E describes them as built “under the auspices of Gond” and secret from the rest of the Sword Coast (which is retarded because printing presses had been described as operating openly on Faerûn in Realms of Valor, set 10 years prior to the 3E FRCS). Their ships are described as carrying “fire throwers” that fire fireballs, and explosive nets that act as mines. To reward them for hiding him during the Time of Troubles, Gond gave them Smokepowder, a comparatively, crappy, expensive version of blackpowder.

Their first mention says they have temples built primarily to serve foreigners, and that they are “energetic” traders with an official traveling government envoy. The 3E FRCS on the otherhand claims the rest of the world knows so little about them that Lantan is “half-mythical” and is wrongfully thought they shun magic, saying they only trade “occasionally” for materials like charcoal and glass (even though glassblowing anything bigger than a bottle is actually fairly high tech, with one piece glass windows not emerging till the Industrial Revolution), then contradicting itself by giving various inventions of theirs that have spread. This disparity would not be reconciled in 4E, as Lantan was destroyed like any other remotely interesting part of Toril in the Spellplague. 5E would retcon this, but merely say the majority of the islands were actually sent to Abeir and are now back instead of further detail the place.