D&D Next culture books:
Culture books modeled on Oriental Adventures. Split OA into different culture books: China, Japan, India, Southeast Asia, Korea.
Real World-based classes, PC races from mythology, themes, equipment, monsters, spells, deities
Several D&D Earth campaign models in each book. (Same world as the Earth glimpsed in various D&D or d20 Modern products.)
Equivalent of Department-7 in each culture book. Knighthood of the Seven in medieval culture, Sodality of the Seven in indigenous cultures.
Also "culturocentric Earth" campaign model for each, where even the world map is shaped how that culture traditionally perceived the world. Like the "Norse alternate world" called Midgard in the Mystara cosmology, which is mentioned in the Northern Reaches Gazetteer
Other campaign models show how to use this material in published D&D Worlds, laying out explicitly which D&D fantasy cultures are based fully or partly on Real World cultures. Acknowledges that some settings (such as Mystara) use RW inspirations directly, while other settings (such as Forgotten Realms, Ravenloft, Greyhawk, and Dragonlance) tend to mix or alter RW elements; and some settings (such as Dark Sun and Eberron) avoid RW influences, but the crunchy bits can still be useful in those settings.
Gamer glossaries for key languages of each culture. For example, in Cathayan Adventures, includes Chinese names for all the relevant D&D classes (e.g. Fighter = Wushi), equipment, monsters, spells, ability scores, skills, etc.; Zipangu Adventures would give Japanese names for the relevant D&D classes, (Fighter = Bushi) etc.
The less popular cultures done as Dragon magazine articles or web-enhancements
Each of these are lovingly crafted, so that each might be the epitome of their genre, while benefiting from being coupled with the streamlined 5e rules system. They aim to be better than all the existing rpgs which feature those cultures.
Emirate Adventures (or Arabian Adventures or Caliphate Adventures; but "Arabian" excludes the Islamic Persian and Ottoman cultures, and "Caliphate" or "Caliphal" may be touchy.)
Sha'ir class
Gamer glossary: Arabic (Representing the Midani language in Toril and the Alasyian language in Mystara); also Islamic-era Persian and Ottoman Turkish.
Campaign Models:
D&D Earth campaign models at key points in Middle-eastern history.
"Emirate Earth": A D&D setting whose map comes from early Islamic world maps, with south at the top of the map.
In Toril: Zakhara, Calimshan, and the Bedine of the Anauroch Desert
Mystara's Emirates of Ylaruam, the Desert Nomads (quasi-Afghan), the Great Hagiarchy of Huyule (quasi-Ottoman Turkish, but the illustration of the Master appears to be evocative of the Ayatollah), and Huyule's colony of Bogdashkan on the Jungle Coast; also gnolls of Gnollistan, lead by Nizam Pasha (Nazim Pasha was Chief of Staff of the army of the Ottoman Empire, and “pasha” is an Ottoman title); the culture of The Manor and of the ancient city of Tuma in B8: Journey to the Rock (e.g the name "Hakeem" and the arabesque architecture in the illustration of the Ghostly Warriors).
Phazaria in the Amber Wastes of Ravenloft
Land of Arir in the stand-alone 1e adventure I9: Day of Al-Akbar
Desert of Desolation, stand-alone 1e adventure trilogy, later placed in Faerun's Plains of Purple Dust; Also, GAZ2 suggested placement in Mystara's Ylaruam
Khinasi of Birthright setting
Bakluni peoples of Greyhawk
Better than Tales of the Caliphate Nights True20
Cathayan Adventures
Wuxia
Gamer glossary: Chinese (Kara-Tur-style Wade-Giles spellings and modern Pinyin spellings); Fighter = Wu-shih (Wade-Giles spelling) and Wushi (pinyin spelling)
Resource: 2e-era Dragon Fist rpg
Campaign Models:
D&D Earth campaign models in key moments in Chinese history
"Cathayan Earth" campaign model, with a world that is really shaped like traditional Chinese worldmaps.
Shou Lung and T'u Lung in Toril
I'Cath in Ravenloft
Ochalea in Mystara
Celestial Imperium/Shaofeng/Sufang of Oerth
Invite Chris Pramas to co-author.
Zipangu Adventures (or Nipponic Adventures)
Chanbara (swordfighting) and other genres
5e Ninja, Samurai, Shugenja classes
Gamer glossary: Japanese (e.g. Fighter = Bushi)
Campaign Models:
Kozakura and Wa in Toril
In Mystara: Empire of Myoshima on Mystara's invisible moon of Patera; also Yasuko barbarians of the Jungle Coast, and the rakastas of the Yazak Steppes in the Savage Coast
Nippon/Ryuujin of Oerth
Rokushima Taiyoo in Ravenloft
3e Rokugan/Lot5R
Better than Legend of the Five Rings and Sengoku
Nubian Adventures
Gamer glossaries: Swahili, Zulu, Kongo, Hausa, perhaps others
Campaign Models:
The Touv in Oerth
Afrik in Ærth
Katashaka continent and Jungle of Chult in Forgotten Realms
The Wildlands in Ravenloft (The Crocodile King is an evil version of the Lion King)
In Mystara: Yavdlom (Swahilis), Ulimwengu (pygmies), N'jatwaland elf-ogres and Simbasta lion-folk in Davania, Tangor in Skothar, Tanagoro (Zulu) in Hollow World
In Dark Sun: the Ivory Triangle
Better than Nyambe. Maybe collaborate with Atlas Games since Nyambe is aleady such a well-crafted Campaign Model.
Celtic Adventures
leprechaun PC
monsters: redcap, banshee
Gamer glossaries: Irish, Welsh, perhaps others
HR3: Celts
Campaign Models:
The Ffolk of the Moonshae Isles in Toril
The Flannae of the Old Faith in Oerth
In Mystara: Principality of Klantyre (Scotland), Province of Redstone (Ireland), Kingdom of Robrenn (Gaul) (and adjacent quasi-Celtic goblinoids), and Thratian Hinterlanders (tribal Conan-style Old Irish/Welsh "Cimmerians")
Forlorn domain in Ravenloft
AD&D1e quasi-Celtic adventures: C4: To Find a King (1985) and C5: The Bane of Llywelyn (1985)
Hibernia in Ærth
Better than Sláine
Koryoan Adventures
Gamer glossary: Korean
Campaign Models:
Koryo in Toril
Nippon Dominion in Oerth (not to be confused with "Nippon" as such, which is Oerth's analogue of Japan. Nippon's "Dominion" is presumably a Korean analogue.)
Turtle Island Adventures
Campaign Models:
Anchorome continent of Forgotten Realms
In Mystara: Atruaghin Clans, Red Orcs, Yazi goblinoids
Rovers/Arapahi of Greyhawk (like Arapaho)
Partial inspiration for Plains Barbarians of Krynn
Resources: 1e Amerindian pantheon, Atruaghin Gazetteer
Gamer glossaries: Mohawk, Lakota, Arapaho, Tlingit, Hopi, Navajo, perhaps others
Suvarnabhumi Adventures (or Golden Land Adventures; Southeast Asia)
Gamer glossaries: Malay/Indonesian, Tagalog/Filipino, Vietnamese, Cambodian, Burmese, Thai, Lao
Campaign Models:
On Mystara: the Indonesian-inspired Siswa Elves in Tracy Hickman's B7: Rahasia module. "Siswa" means "Student" in Indonesian (and they are called "Elven students"), and other Indonesian names: "Rahasia" (='secret, confidential') and "the Rahib" (='monk').
On the invisible moon of Patera of the World of Mystara: Selimpore (Singapore), Malaycalog (Philippines), Kompor-Thap (Cambodia), Surabayang (Malay)
Malatra, the Island Kingdoms, and other lands in the south of Kara-Tur of the Forgotten Realms
Babylonian Adventures (or Mesopotamian Adventures)
Campaign Models:
Unther of Forgotten Realms (pre-Spellplague)
In Mystara: Nimmur and Enduks of Eshu
Ishtarland in western Oerth
Babylonian pantheon from 1e
Babylonian deities from 2e Return to the Keep on the Borderland
scorpion-folk
Gamer glossaries: Akkadian, Sumerian
Biblical Adventures
D&D Earth's equivalent of Biblical Palestine
campaign model: Magiocracy of Herath in Mystara (Hebrew-speaking shapechanger spider-folk (araneas))
Gamer glossary: Ancient Hebrew
Better than Green Ronin's Testament
Tawantinsuyu Adventures (or Incan Adventures or Andean Adventures)
Gamer glossaries: Quechua and Aymara
Campaign Model: Oltec of Mystara's Hollow World
Non-WotC: Southern Cross continent mentioned in Northern Crown setting.
Amazonian Adventures (perhaps merge with Tawantinsuyu Adventures?)
Gamer glossary: Guarani, Old Tupi, Yanomami
Campaign Models:
In Mystara: Phanatons of Jibaru (on the Savage Coast), Manacupuru (in Davania), and Caymen of the Blight Swamp in AC2: Combat Shield & Mini Adventure (caimen-folk, based on the Galibi Carib culture of South America:) https://en.wiktionary.org/wiki/caiman
Lopango: The Land of Fire in Forgotten Realms
Turanian Adventures (or Tatarian Adventures; Central Asian Mongols, Turkics, and Scythians)
Gamer glossary: Mongolian, Old Turkic, Scythian (or invented Scythian-style names, since the language is barely recorded)
Campaign Models:
In Toril: the Horse Plains; also Murghôm (said by Rich Baker to be partly evocative of the Cossacks/Turanians of the Conan stories). Also, the Ama Basin peoples are parallel to the Tarim Basin peoples (could be grouped in Hyperborean/Siberian adventures instead.)
In Mystara: the Ethengar Khanates, Yellow Orcs, and hobgoblins of Hobgobliny; also Jennites (Scythians) of Mystara's Skothar continent and in the Hollow World
In Oerth: Tiger Nomads and Wolf Nomads
In Krynn: The Khanate of Khur in Ansalon; and on the continent of Taladas: the Uigan, Purgi, Pureshk, Kazar (quasi-Kazakh), and Alan-Atu (quasi-Buryat) tribes, and the Tamire Elves
Hellenic Adventures
Dryad, Centaur, Satyr, Minotaur PC races
monsters: lamias, titans
Gamer glossary: Classical Greek
HR6: Age of Heroes
Campaign Models:
D&D Earth at key moments in Greek history (Trojan War, etc.)
"Hellenic Earth" where the world is really shaped like the ancient Greek worldview, like these Homeric worldmaps.
Mystara: Minaeans (Minoans) near Skothar; Milenian colonies of the Grass Coast; Cathos and Vacros; Milenians and Traldar of Hollow World
Chessenta of Forgotten Realms
Tharquish Empire in Oerth, based on how it's portrayed in the Black Moon Chronicles.
Better than Green Ronin's Trojan War
Northern Adventures (Norse-Germanic)
Gamer glossaries: Old Norse, Anglo-Saxon, Old High German, Old Saxon, Gothic
1e Norse pantheon
HR1: Vikings
3e Asgardian pantheon
Campaign Models:
The Northmen of the Moonshae Isles and the Uthgardt Barbarians of Forgotten Realms
The Northern Reaches of Mystara (Vestland=Sweden, Ostland=Denmark, Soderfjord=Norway) and the Heldann Freeholds (Iceland) before the invasion of the Knights. Also, the Midgard "Norse-centric" Outer Plane mentioned in GAZ7.
Rjurik of Birthright setting
The Ice, Snow, and Frost Barbarians of Oerth
Partial inspiration for Ice Barbarians of Krynn
Hyperborean Adventures (Finnish, Saami, Siberian, and Inuit-Aleut)
Finnish pantheon from 1e Deities & Demigods, incl. Loviatar
Siberian pantheon(s)
Inuit pantheon
2e Angakok wizard kit (Inuit shaman)
Campaign Models:
In Toril: the Ulutiun people (Inuit) of the Great Glacier; the Northern Wastes (Siberia); also the realm of Vaasa seems to have originally been conceived as quasi-Finnish, so perhaps might still have some Finnish elements.
Gamer glossary: Finnish, Inuit, perhaps others
Eastland Adventures (Slavic, Hungarian, Gypsy/Romany, Albanian; Caucasus?)
Taltos (Hungarian shaman) and Gypsy classes or themes, Baba Yaga, Kostchtchie
Ravenfolk and Goatfolk PC races
Slavic pantheon, Magyar pantheon. (Armenian and Georgian pagan pantheons?)
Campaign Models:
Rashemen of Forgotten Realms
Rhennee gypsies and Stonefist barbarians of Greyhawk
Vosgaard of Birthright setting
In Mystara: Traladarans of Karameikos, Boldavia, and the City-States; the Goatmen of Kavaja; and the Duchies of Vyostograd and Stamtral in Norwold, from CM4: Earthshaker
Barovia, Nova Vaasa, and Vorostokov in Ravenloft
James Wyatt's Petroyeska campaign setting
Gamer glossary: Old Slavonic, Russian, Romany ("gypsy"), Hungarian, Romanian, Serbian/Croatian, Albanian, perhaps others
Tales of the Old Margreve for Pathfinder
Pharaonic Adventures (or Egyptian Adventures)
Gamer glossary: Ancient Egyptian names for all the relevant D&D classes, races, equipment, spells, monsters, etc
Campaign Models:
Mulhorand in Forgotten Realms
Erypt of Oerth
Hutaakans and Thothia in Mystara; Nithia in the Hollow World
Sebua and Har'Akir in Ravenloft--featured in the video game Ravenloft: Stone Prophet
In Ærth: the land of Ægypt/Khemit, featured in Gygax's Necropolis d20 adventure by Necromancer Games
Better than Hamunaptra: Egyptian Adventures and Gygax's Khemit
Roman Adventures
HR5: The Glory of Rome
Campaign Models:
Thyatian Empire in Mystara (Byzantine, but mixed with some ancient Roman features)
The Minotaur League (on the continent of Taladas in Krynn)
James Wyatt's Imperium Romanum and Shield of Faith settings
Gamer glossary: Latin (also used for Old Oeridian)
Better than Green Ronin's Eternal Rome and Adamant Entertainment's FVLMINATA: Armed With Lightning
Arthurian Adventures
The "Matter of Britain"
Campaign Models: How to use Cormyr as an Arthurian Campaign Model
Better than Pendragon. Maybe even collaborate with Greg Stafford.
Carolingian Adventures (or Frankish Adventures)
The "Matter of France"
HR2: Charlemagne's Paladins
Campaign Model: Kingdom of Eusdria in Mystara
Jambudvipa Adventures (or Bharatian Adventures)
monsters: bhut, juggernaut
Gamer glossaries: Sanskrit, Tamil
1e and 2e Indian pantheons, Ascetic class in 2e Legends & Lore
CD&D Thug class in Champions of Mystara boxed set
Kolhapur in stand-alone 2e adventure Star of Kolhapur
"Rhino's Armor, Tiger's Claws" Dragon #189
"Caste of Characters", "Monsoons & the Power of Om", and "Bazaar of the Bizarre" in Dragon #226, 227, 229
Campaign Models:
Sind, Jaibul, and Glantri's principality of Krondahar in Mystara; Rajahstan on the invisible moon of Patera; Shajapur in Hollow World
Utter East of Forgotten Realms
Zindia/Zahind of Oerth
Sri Raji in Ravenloft
3e Mahasarpa campaign
Better than Green Ronin's Mindshadows
Anahuac Adventures (or Mesoamerican Adventures)
Campaign Models:
Olmans in Oerth
Maztica, formerly in Toril, now in Abeir
In Mystara: Viper/Tiger Clan of the Atruaghin Clans; Schattenalfen; the orcs of Oenkmar; Oceotl catfolk; Azcan Empire in the Hollow World
monsters: sahuagin, ixitxachitl
Gamer glossary: Classical Nahuatl and Classical Maya
Persian Adventures (pre-Islamic)
Gamer glossary: Ancient Persian
Himalayan Adventures
Yeti, Yak-folk
Gamer glossaries: Tibetan and Nepalese
Campaign Models:
Tabot (Tibet) and Ra-Khati (Nepal) in Toril
In Mystara: Lhamsa in the Principalities of Glantri, and the Snow Pardasta catfolk
Dreamtime Adventures
Campaign Models:
Osse continent of Forgotten Realms
Wallara chameleon-men in Mystara
The continent of Magmur in Ærth
Gamer glossary: Western Desert Language
Oceanic Adventures (or Island Adventures, or South Sea Adventures, or Pacific Adventures; Micronesian, Melanesian, and Polynesian)
Gamer glossaries: Hawaiian, Maori, Tok Pisin, perhaps others
Campaign Models:
Kara-kara (quasi-Melanesian) of Isle of Dread (located in Mystara, Oerth, and Feywild of Nerath)
Mystara: Makai (Hawaiian) of Ierendi and the Hollow World
Medieval Adventures (medieval western & central Europe of D&D Earth).
Covers post-tribal, pre-renaissance Italian, French, Spanish, Portuguese, German, Dutch, British cultures (though Arthurian Adventures is its own genre; perhaps Carolingian genre is included in Medieval Adventures)
Similar to Magical Medieval Society: Western Europe by Expeditious Retreat Press.
D&D Earth equivalents of Christian clerics, etc (Touches on real world religions in the same way that the Urban Arcana modern campaign model would)
Resources:
2e HR: Crusades
3e Robin Hood mini-setting from Dragon Magazine
Campaign Models: (though most D&D countries are quasi-medieval, only those which are mostly inspired by Real World medieval western European countries would be featured in this book)
Robin Hood
Crusades
Amn (Spain) in Faerun
Narvaez (Inquisition Spain) in Mystara
several medieval Western cultures in Ravenloft
Better than Green Ronin's Medieval Players Manual
Renaissance Adventures (post-medieval, pre-industrial western and central Europe of D&D Earth)
Elizabethan England, Italian Renassiance, Age of Reason, Three Musketeers, etc.
Resources:
AD&D2e HR4: A Mighty Fortress
Campaign Models:
Age of Adventure campaign model from d20 Past
In Mystara: Bellayne (Elizabethan English catfolk), Renardy (Absolutist French dogfolk), several Glantrian principalities (Averoigne/France, Caurenze/Italy, Fenswick/England, etc.), Minrothad Guilds (East India Trading Company)
Chondath in Faerun (renaissance Italy)
several Renaissance Western cultures in Ravenloft
Better than 7th Sea
New World Adventures (or Colonial Adventures)
Focuses on the settler/immigrant cultures of North and South America, from the 1500s through the 1700s. The indigenous cultures are covered in D&D Turtle Island Adventures, Anahuac Adventures (Aztec and Maya), Tawantinsuyu Adventures (Incan), and Amazonian Adventures.
Campaign Models:
New Waterdeep (British North America) and New Amn (New Spain) in Toril
Mystara: Texeiras (Brazil), Almarron (Mexico), Guadalante (Argentina), Torreon, Nouvelle-Renardie (Louisiana), Free City of Dunwick and Richland (British colonies) in the Savage Coast
Capoeira "Battle-dancer" PC class; other colonial American classes.
If it's too much to fit North and South America in one book, then perhaps include all South American cultures (immigrant and indigenous) into a single Tawantinsuyu Adventures book.
Better than Northern Crown: New World Adventures by Atlas Games; maybe collaborate to make Northern Crown a campaign model.