Here are the references to Souragne from the BoS series:
Book of Sorrows
Vistani Chess
Anton Misroi is said to have a drotche set made of wood carved from a bloodwood, a type of tree found only in the swamps of Souragne, and a fire-blackened oak that formerly housed a dryad.
Simon LaFleur
A JuJu Zombie NPC created by Chicken Bone. Lots of background info !!!
The Boccoru
-a chracter kit/specialty priest class/Druid variant
-Souragnean loa are nature spirits of the swamp
-Misroi is loa of death / Lord of the Dead,
-the Maiden of the Swamp is loa of Life (a hamadryad with spellcasting as 9th lvl boccoru/9th lvl mage)
-the loa of foxes, Bushytail is found in Richemulot!?!
Children of the Bayou
New Horrors for Souragne: Werepossum, Nightcrawler, Uncle Skeleton, Weeping Willow
Children of the Light
Ravenloft PC rules has an entry for Souragne:
Souragne
Cultural level: Chivalric.
Races: Human.
Classes: Any. Priests must be shamans (pages 34 to 38 Spells & Magic), wizards must be specialist necromancers.
Kits: Animal master, beggar, mariner, merchant, mystic, pirate, smuggler, thug.
Characteristics: All but upper class characters (10%) receive half normal starting money.
The Gothic Earth guide to Voudou
by Bil Boozer pg.173 of the BoSor. Although it's not based on Souragne as such. much of the article is quite useful due to the Loa worship of Souragne and the relevant real world parallels, not to mention saving a lot of time researching the topic of the Voudou from the ground floor up for ideas.
Book of Sacrifices
Myths of the Mists
Souragne, Nova Vaasa, Hazlan (Eric Daniel)
In the swamps of Souragne, the walking dead are known to lurk within the darkness of the swamps, but sometimes ghosts are said to walk the streets of Port d’Elhour. Some merchants of Souragne have created little clay fetishes, called watchmen, to sell to people. These watchmen supposedly have to ability to ward off spirits when carried. The watchmen are little clay figurines, roughly man-shaped, usually in plain fired clay but sometimes glazed in bright colors. Most of these watchmen have no power, but occasionally there have been reports of a ghost being driven away from someone with a watchman. Whether this has to do with the watchman or something else is unknown.
The fetishes have spread to some of the other domains, notably Nova Vaasa and Hazlan, where they are mostly considered to be curiosities and purchased as a decoration.
The Zanango Society
A secret society worshiping Anton Misroi. Lots of background info !!!
Book of Souls
Saga of the Mists
has an entry for Souragne:
Souragne
Heroes: Souragnien shamans use the Primary Spheres of the Healer, the Druid, and the Bishop, with the Secondary Spheres of the Monk and the Missionary. Heroes with a Wealth score of 6 or less find that their final score is reduced 1 point due to the strong social divisions and widespread poverty of this swampy isle.
Lord: Anton Misroi
Nature: Sadistic and Selfish
Demeanor: Dramatic
Reputation: Adventurer (6 Quests)
Social Status: Aristocracy (8)
Ph: 7B Co: 9B In: 8C Es: 6C
Damage: +8 Defense: 0
Special Notes: Anton can transfer himself between plants at will and regenerate himself by merging with the swamp. He can cause death or disease at will, speak with the dead, animate as many dead as he can find corpses (and the swamp is littered with corpses), and duplicate any necromantic effect with the dance of the dead, which takes him only one minute to peform.
Voodan Zombie
not undead. Includes details on the creation.
Book of Shadows
The Order of Twilight
Rumors have it that other cells exist in the Islands of Terror, most likely in domains such as G’Henna, Souragne and Vorostokov.