Six Strange Rivers cross a great plain, flowing from some mysterious source to the great churning ocean. Settlements cling to the banks of these rivers; ferries and barges sail them - but only a few will travel to their source, or to their dissolution in the great ocean.
Here and there, the rivers come to a junction, a joining. It is at such places that settlements spring up, and of such things the sages have written.
Thus, at the join of the Styx and the Bhallduin, the ash-grey waters of the one flow into the pearlescent waters of the other, forming the 'Dovetide'. The city there is called Eliombré.
Those who dwell there have wandered far from mundanity, or are the descendants of those who have done the same - be it singly or as part of a great exodus.
Two principal groups rule in Eliombré; Solar Cultists; lawmakers and craftsmen of fine instruments - and Merchant Princes from the marches of the Underworld; fatalistic, phlegmatic and exacting. There is a sort of complimentary constitution to accommodate both in the functions of government.
Each group has its share of river-washed: Styx-washed nigh-invulnerable fighters and Bhallduin-washed far-seeing scouts or tacticians. Occasionally, one washed in the Dovetide will be both to some degree.
A Word on Adaptation: The initial post, Six Strange Rivers, had (like the Styx) rivers to be crossed. Here, the rivers flow from [the Underworld, the Celestial Realm, &c] into the great ocean of mingling and dissolution. The ferryman - be it Charon or a Solar Hierophant or anything else on the list - takes you upriver to that place at the usual cost on the usual boat. There's probably an ornate wharf (or waterfront shrine, or shunned promontory with a ritual fence covered in apotropaic charms) where the ferry will dock according to some occult timetable. The access to that up-river other-land is part of what brings the crackpot, the fanatic, the mystic, the treasurehunter and the adventurer to the city.
The rivers may be crossed by regular watermen, but the river-washed will excel at this; mundane ferries often have some motif or shrine or decorative element made to evoke the supernatural ferry.
The River-washed are less common than 'A Child dipped in the River' would suggest. Immersing your child in the water is a spiritually, psychologically and probably physically gruelling task; the mother, father or other principal childrearer that could stand to do it was probably going to raise a fairly decent specimen of humanity no matter what. Children can be too old or too young for the river to have an impact; they can be kept in the water for too short a period or have their bodies covered against the river's influence. All of which is to say, those living by the Styx cannot well produce an invulnerable legion of soldiers for their wars, for all that they might muster a company of iron-hard footmen.
At the join of ... the Styx and the Izonn ash-grey waters flow into pellucid waters, producing the Milkglass Cataract.
The city there is called ... Milkglass.
Dwelling there are ... a tribe of Harpies and the Harpy-blooded, claiming descent of the Kindly Ones; they possess a strong sense of justice and retribution and are more than eager to engage in duels or down tools to engage in the work of a posse. This hot-blooded band are balanced by an academy of philosophers who are very keen to work out what exactly justice consists of before anyone decides to go and carry it out.
These two balance power by ... ensuring that there are goodly quantity of the River-washed in each camp. A level-headed philosopher washed in the Styx will resist the blows of Harpy-blooded hotheads and the Izonn-washed will remain self-aware even in the midst of an episode of mob justice.
The River-washed ... are carefully distributed between both groups.
At the join of ... the Styx and the Novar ash-grey waters flow into sky-blue waters, producing a effect sometimes called the Perpendicular Horizon.
The city there is called ... Antegarten
Dwelling there are ... the old and the young; or, perhaps, those close to life and those close to death. There are no formal groups, parties or camps - you merely show up to Antegarten and find your place.
These two balance power by ... alternating seasons; the spring and summer are given to the old to counter any natural advantage of the young. The vigour of the young is set to oppose the harshness of winter.
The River-washed ... the Styx-washed guard the young; the Novar-washed delight the old.
At the join of ... the Styx and the Thyrss ash-grey waters flow into peacock-green waters producing Hangover Bend.
The city there is called ... Dionest.
Dwelling there are ... sober burghers who live quietly, conscious of their mortality and sustained by the sale of liquor. Their customers are live-fast die-young types after a good time, and only occasionally aware - very aware - of their mortality.
These two balance power by ... the burghers are very good at stocking their cellars and keeping shop, but utterly abysmal at marketing. No-one would come to Dionest if it weren't for a string of charismatic gourmands and poets, who in turn need a good line of credit to keep the party going.
The River-washed ... persist in Dionest, where even-keeled iron-stomached vintners are matched by invulnerable gluttons.
At the join of ... the Styx and the Sennus ash-grey waters flow into marl-red waters at Moctarm Lock.
The city there is called ... Rustfork.
Dwelling there are ... the members of a hierarchical mortuary cult, whose ornamental liturgies are contrasted by a grim ultra-pragmatic military association.
These two balance power by ... channelling all disputes into raiding and expansion. One party gets to fight and persist, the other gets to bury more bodies and build more mausoleums.
The River-washed ... feed the demands of soldiers and morticians both.
At the join of ... the Styx and the Eilex ash-grey waters flow into indigo waters at Dorm Reiall.
The city there is called ... Æcoronopolis.
Dwelling there are ... memorialists, chroniclers and relic-keepers who care for a vast treasury of discarded artefacts; attending them are hero-worshippers and ambitious students of history drawn by the archives.
These two balance power by ... electing members to a semi-annual senate with a hebdomadal council for executive matters.
The River-washed ... are set to use as invulnerable guardians of ensorcelled blades, mind-capturing wands and kingly amulets - or go off to seek their fortune as lords from the city of lord's-leavings.
***
At the join of ... the Bhallduin and the Izonn pearlescent waters flow into pellucid waters at Coruscant Ford.
The city there is called ... Urbs Excelsior
Dwelling there are ... priestly philosophers and philosophical priests. Sometimes you can tell them apart by dress, but then the priests enter a season of asceticism and penitence and the philosophers have one of their occasional formal ceremonies and everyone seems to change clothes.
These two balance power by ... a series of highly structured quasi-theological public debates. The agenda for these is set by a closed committee who also regulated the canon of relevant texts for debate.
The River-washed ... are highly sought after as arbitrators and chairs of meetings.
At the join of ... the Bhallduin and the Novar pearlescent waters flow into sky-blue waters at Cumulus Point.
The city there is called ... Treva.
Dwelling there are ... sun-worshippers and nature-worshippers at each other's throats. The former are seen as inflexible fanatics, the latter as inconstant savages - or is it the other way round?
These two balance power by ... A) a 'non-lethal' football game rather like Calcio storico, B) an assembly formed by sortition (the pool of potential assemblymen being thinned out by football injuries) using carefully desecrated ballot-boxes and C) Pillarisation.
The River-washed ... are scattered through the ranks of either faction, rising or falling as the fates allow.
At the join of ... the Bhallduin and the Thyrss pearlescent waters flow into peacock-green waters at Galanthum.
The city there is called ... Malaquatz.
Dwelling there are ... astronomers and hobbits, in so many words. Rural plenty (and those seeking same) alongside those who have fled light pollution and distractions to chart the course of the immortal stars.
These two balance power by ... the exchange of fresh produce for meteorological information and records. Astronomers will also sometimes act as neutral celestially-minded arbitrators of disputes.
The River-washed ... become exceptional astronomers or remarkable chefs.
At the join of ... the Bhallduin and the Sennus pearlescent waters flow into marl-red waters at Silver-Stroke.
The city there is called ... Occidenaburgh.
Dwelling there are ... astrologers and the ill-fated, sniffing out ways to avoid a doom or deny a wyrd - or merely to make the most money possible in the meantime.
These two balance power by ... enabling one another. Crotchety soothsayers leave through dusty texts offered by haunted lone swordsmen, then send them off to find rune-carved sceptres or lost cities.
The River-washed ... are split. The clear-sighted normally want to leave Occidenaburgh at the first opportunity; those who will die in battle will often leave to pursue lucrative, dangerous and non-military roles.
At the join of ... the Bhallduin and the Eilex pearlescent waters flow into indigo waters at Lost Toga.
The city there is called ... Lost Toga.
Dwelling there are ... the envoys, knights, heralds, courtiers, plenipotentiaries, shoguns and special agents of a hundred different 'Sun Kings'. They all await the return of their respective monarchs from the Isle of Crowns. The gathered loyalists have produced successive generations - many of which have embraced a culture that hold in regard the divine sun that anoints kings rather than those with an attachment to the person of the monarch.
These two balance power by ... effectively, a rolling continuous Investiture Controversy relieved with the occasional joust.
The River-washed ... tend to spend their days going from court to court in Lost Toga keeping everyone going in the same direction.
***
At the join of ... the Izonn and the Novar pellucid waters flow into sky-blue waters at Hrothgar's Dam.
The city there is called ... Haphn
Dwelling there are ... inquisitors and innocents. Refugees from war-torn regions flow into a land of relative safety, where a henotheistic religion polices itself (technically, guides the secular power) very carefully. The desire to protect, preserve and purify means that believers are given powerful incentives to gain and wield more power for the protection of their charges.
These two balance power by ... a queasy cocktail of generosity, vocal support, shows of helplessness and fervent processions.
The River-washed ... find a place in either an active or contemplative order of monks.
At the join of ... the Izonn and the Thyrss pellucid waters flow into peacock-green waters at Nettlebed Sluice.
The city there is called ... Pinbrigge.
Dwelling there are ... serious scholars who only use mind-altering substances under carefully controlled conditions who resent the presence of an assortment of drug addicts and other degenerates on their doorstep.
These two balance power by ... a quantity of Izonn-washed in each camp to keep the scholars to their study and the masses to their minimum efforts.
The River-washed ... can make an excellent living testing and selling drugs.
At the join of ... the Izonn and the Sennus pellucid waters flow into marl-red waters at Crimson Lake.
The city there is called ... Calvyne
Dwelling there are ... the bleak-eyed visionaries who have seen the end of all things and the bleak-eyed geometricians who have measured all things and know where they will lead.
These two balance power by ... competitive nihilism and a joint appetite for strong liquors.
The River-washed ... count down the hours.
At the join of ... the Izonn and the Eilex pellucid waters flow into indigo waters at Pied-Mead.
The city there is called ... Platon.
Dwelling there are ... philosophers and their guardians.
These two balance power by ... competitive examination in arithmetic, geometry and athletics.
The River-washed ... either become administrators or leaders.
***
At the join of ... the Novarr and the Thyrss sky-blue waters flow into peacock-green waters at Qurtoise ford.
The city there is called ... Qurtoise.
Dwelling there are ... Austere pastoralists who write poetry and live on mutton and milk, trading with lackadaisical agrarians who create paintings and live on millet and samogon.
These two balance power by ... transhumance patterns of migration keeps the shepherds at a distance; the quality of their verse and the charm of the Novarr-washed win their good name in the settlements.
The River-washed ... either win plaudits for their charms or stay healthy despite poor meals.
At the join of ... the Novarr and the Sennus sky-blue waters flow into marl-red waters producing the Amethyst Streak.
The city there is called ... Kadeks
Dwelling there are ... the maimed, the aged and the ailing - bringing hard-won knowledge and secrets of the deepest dungeons to a city of healers, circled with aromatic gardens of medical herbs.
These two balance power by ... the customer is always right; the customer is also tormented by old wounds and must surrender to his physicians and carers.
The River-washed ... provide good-tempered nurses - and a source of future patients.
At the join of ... the Novarr and the Eilex sky-blue waters flow into indigo waters at the Gradation.
The city there is called ... Meixhia
Dwelling there are ... gardeners, who maintain their flourishing orchards and flower-fields in careful ignorance of the outside world. The curious, the disruptive, the ambitious, the pioneering are channeled into manual labour; passing mercenaries and adventurers are captured and forced into slavery.
These two balance power by ... an iron grip is maintained by the gardeners - and the mercenaries give them ample reason to do so.
The River-washed ... are set as judges, for their discernment - or their innocence.
***
At the join of ... the Thyrss and the Sennus peacock-green waters flow into marl-red waters at Popinjay Channel.
The city there is called ... Roan Hill.
Dwelling there are ... a Maenad-blooded tribe that train giant leopards and a tribe, reputedly descended from ogres, that rear long-lived mastodons that house entire families.
These two balance power by ... forming something like political parties dedicated to either trade or raiding.
The River-washed ... maintain life and vigour despite the customary intemperance following a raid, or attend on caravans, placing their doomed lives between precious goods and raids.
At the join of ... the Thyrss and the Eilex peacock-green waters flow into indigo waters at Rohelsinine.
The city there is called ... Tskoff.
Dwelling there are ... A series of clans, septs and extended families. They dwell in an assortment of sprawling compounds centred around large banqueting-houses or mead-halls. Communal meals and regular, ritualised gift-giving are the norm.
These two balance power by ... there are gift-givers and the heads of households; their ambition is checked by the needs and requests of their necessarily many friends, relations and servants.
The River-washed ... the Eiliex-washed rise to positions of strength in Tskoff; the Thyrss-washed act as hardy rangers and outriders - capable of taking long journeys in the wild, and always willing to return to the comforts and rewards of home.
***
At the join of ... the Sennus and the Eiliex marl-red waters flow into indigo waters at Mavorsferry.
The city there is called ... Ciudad Zmeyti.
Dwelling there are ... those quarrelsome folk who were (by legend) produced by strewn dragon's teeth and a conquering race of dragon-riders.
These two balance power by ... the former can become something like ungovernable; the latter have access to the ultima ratio regum, but this is not very useful when one wishes to conquer rather than slaughter. Tooth-clenched compacts and the more Hobbesian (in the proper sense) social contracts are the norm.
The River-washed ... the Sennus-washed are a very useful tool against dragon-riders. You are going to die in battle anyway - why not make it here and now for an issue very close to your heart? The Eilex-washed become very frustrated and frequently seek their fortunes elsewhere.
Mesopotamia is, of course, between two rivers.