Some players would rather not want to get tied down with the lore in the books, and instead create worlds of their own. Others modify lore in existing worlds to suit their own needs. I've created a world all my own called Axeoth. Heavily modeled after Warhammer Fantasy, Axeoth is a hybrid of both High Fantasy and Dark Fantasy. Like Eberron, Axeoth tries to avert a medieval setting. Unlike Eberron, it's tech is based on the renaissance, with a number of exceptions. Like Warhammer Fantasy, relationships between nations is rocky, war is common, superstition rules humanity, and the difference between natural deformities and mutations are not easily known. Like Warhammer Fantasy, Chaos is the ultimate force of evil and there are 4 dark gods who serve as the greater scope villains. UNLIKE Warhammer Fantasy, the nations relationships with each other are somewhat better. Mutations are not as common, and gods not associated with Chaos are just as powerful as the 4 dark brothers.

Quests range from grand in scale to simple but powerful. Grand quests tend to involve traveling long distances to defeat a great evil, rescue someone, breaking a curse, finding hidden truth's or knowledge, or finding plot coupons. High Fantasy, Heroic Fantasy, and Dark Fantasy are prominent in these quests and sometimes overlap, creating more colorful quests that anyone could join in regardless of whom they are.

But other quests are smaller in scale, but have more emotional weight. These quests often involve fighting corruption in society, protecting settlements from bandits and thugs, saving a dying child, reuniting friends and family amid a harsh setting, acts of kindness, highlighting the struggles of the poor, downtrodden, social outcasts, and homeless. And standing up to those in power. In other words, quests that reflect real life.

What have you created?

good lord... my world is over 35 years in the making...
Lets see... 200+ playable races (slightly less after converting to 5es sub-races format)
4 major land masses each with its own multi-culture kingdoms and empires (and until recently kept separated by mystic barriers that are now failing)
an intensive history that includes no less than 5 world wide cataclysmic events that set back technology and society in addition to 15 distinct Eras.
each major city populated with no less than 300 named npcs

you would be surprised how much info a single continuity can accumulate over 3 and a half decades of steady gaming

Whoa! What's it called?

The Realms (I have not really found a name for the world that seems to fit better as yet)

Here, this is my setting, as well as a setting adapted from the Forgotten Realms (but changed a ton).

Around 25 years ago I fell in love with the setting of Mystara. I used that as the basis for my own world. I updated it some to include some of the things from the 2e adaptation of the world. I also dropped a couple of less explored continents, added a couple of my own, added a 6,000 pre-history to the 5,000 history the world already had. The planet now has a massive geas that affects every sentient species preventing them from interbreeding with anything that doesn’t already have some genetic link to their species. I added several races as playable: Half-Dwarfs, Half-Gnomes, Half-Goblins, Half-Hobgoblins, Half-Ogres aka- Ogrillon. So Half-Elves can breed with Elves, Humans, Hin, and other Half-Species as an example, but no one else. If a Half-Elf and a Half-Orc interbreed, the children just come out as human. (The word “humie” [pronounced ü-mē] is actually the Orcish word for “mongrel.”) Dragonborn are related to Kobolds the same way Hobgoblins and Bugbears are related to Goblins.

I honestly couldn’t include everything here.

My campaign is set in the world of Arthurian knights, taking place shortly after the King's death:

'10 years ago, the continent of Avalon enjoyed a relatively stable peace between the main nations of the world. The most well-known of these was the Human country of Camelot, which was ruled justly by the wise King Arthur. Though not a perfect man, Arthur strived to do good, and peace was protected by his Knights of the Round Table. 

However, a dark enemy known as Mordred was plotting to take the throne from within and, after he gathered his followers, Mordred launched an assault on the city itself. This was lasted nearly a month, with the final battle coming after Arthur was betrayed and left vulnerable to the blade of the Mordred. Goading his subdued and defeated enemy, with the last of his breath, King Arthur lashed out and struck a fatal blow; both Mordred and the King himself died that day. Shortly after, with no heir to the throne and the King’s brother missing, the crown fell to King Tarnos. With his rule, came the increasing distrust of the other races and soon came the disbanding of the Knights of the Round Table.

Now in the present state, the political landscape is tumultuous. Without Arthur’s diplomatic tact, and the knowledge that there were traitors during the last great battle in which Arthur himself fell, the main 4 races are in a tentative state of peace. With suspicion prevalent amongst the leaders of each country, it would not take much to spark the fires of war between them, bringing the continent of Avalon to its ruin. Indeed, there may be those behind the scenes watching intently, waiting for the moment to use this suspicion to accomplish their own insidious goals...'


The world itself is a mixture of inspiration from common Dnd lore and the Critical Role Exandria setting, mish-mashed into a very much 'My First Campaign World' setting with clearly defined countries and locales to make it easier for NPC and encounter generation.

My homebrew world is called Borrelia, and it's mostly high fantasy/post-apocalyptic, with some dystopian as well. Just over a hundred years before the present day, after a failed ritual, demons from the Abyss entered the world through a portal, corrupting the very world around them. The Allied Races (humans, elves, and dwarves) fought to together against this threat, and many other races, such as the hobgoblins and orcs, fought against the demons on their own. But even the combined power of all the mortal beings in the world- and many immortal ones- was not enough to defeat the demons. Many elves fled across the sea, to their native lands, or into the heart of the sylvan Redbranch Woods, and many dwarves retreated to their strongholds under the earth. All seemed lost.

But as the demons steadily advanced, destroying all in their path, the gods, good and evil alike, knew what had to be done. Together, they combined their powers, driving the demons back to the Abyss and sealing them there forever. But the energy that this task had taken made the gods fade, tilting the balance of the world towards a slow road to annihilation.

After the war, the once-great human kingdom of Galoron was in shambles. The world itself had been twisted, turning the vast Forest of Mists into the Forest of Shadow, and much of the Gilded Plain into the land that became known as the Blood Plain. The damage caused by the Demon War seemed to be irreparable. But then a new hope emerged. A cruel, twisted hope, but hope nonetheless.

This hope came in the form of four great archmages who called themselves the Sorcerer-kings, and indeed they were kings, for they had taken control of the ruined kingdom of Galoron and pieced it back together. But they were not just or good. They ruled with fear, not kindness. No one could supplant them, as they were masters of the arcane, no one could oppose them, as all other kingdoms lay broken around them, and they could not simply be waited out, as they had unlocked the secrets of immortality. But only a year after the rise of the Sorcerer-kings, an unknown entity known only as "the Enigma," started a rebellion: the New Dawn.

While the Sorcerer-kings believed that people could not be trusted to make the right choices without help from a wiser being, the New Dawn believed that the people should make there own choices, and be trusted to do the right thing. While Galoron had far more power at its disposal, the New Dawn was cautious and elusive. The Sorcerer-kings sent many agents to find the location of the New Dawn headquarters, but none were successful. And so, for a hundred years, these two powers have waged war, with the fate of the world caught in between them.

My campaign is set on a continent I name Erayath primarily in the countries of Kirune and Wivora. The premise currently is that there is a an sub branch of drow (who I've dubbed the Ungoleth) have a secret plot brewing to bring about the will of Lolth–– a religious endorsed genocide meant to venerate the most pure and worthy severants. I decided to create an offshoot of drow because I think fantasy racism is dumb and wanted there to be a motivation to start chaos that's not just because their race is inherently evil. The rest of the drow live amongst the common people and are just like everyone else, they are known as the Unvalo. The main players are high priestesses of Lolth, Zurine and Nabila, who are unleashing undead to attack the countries and try to kidnap clerics, priests, and priestesses of the protector gods because she was betrayed by them and has a blood lust for sacrifice. This is the major drive for my players-- to prevent the disappearances of the clerics and stop the high priestesses from attaining an ancient powerful relic that would allow her to gain enough strength to get her revenge on the protector gods. 

I reworked some of the god lore to fit my plot and drew on some 2e and 2e stuff and just kind of mixed it together. I took some of the harbinger coup story and gave Lolth the goal of ruling over multiple plains so she could spread violence and chaos. She's embittered by her banishment from the main pantheon and seeks to kill (mainly) Corellon and the Raven Queen. That's were I took some of the other lore, that the raven queen was created during the planar wars. Lolth has a serious grudge against her and wants to retake shadow fell, which in my game she once presided over. 

I created a super detailed world with a ruling system and an in depth economy. I have months and holidays that are significant, as well as historical events that drive some of the story forward. prior to the campaign there was a large multi nation war 200 years ago that changed a lot of the relationships between several nations that still impact them currently. The government council of nine in Wivora plays a significant role in the actions of my players and have a lot at stake based on whether they fail or succeed. I've created 4 intricate thieves guilds; the bloodrats, shadow hoods, the strangers, and the friends of the reckless (these guys are pirates.) I've also instated a main military with sub branches--the Stone guard and the city watch AKA the cerulean shields. There are 2 main monastic orders that have different 5e traditions; order of the undying flame and the order of the faceless smite. 

There are political factions in Kirune (which is a nation tearing itself apart due to the drow conflict as well as government corruption. There is the Svikari Conclave which are the king's advisors. They are a corrupt group of magic practitioners (yeah I borrowed a bit from Critical Role's Cerberus Assembly) who suppress any word of war and keep the people in the dark. Their opposition (and this is because one of my players wanted to be funny) is called the Worker's Ascension Party-- WAP (yes like the Cardi B song...) These also motivate much of the plot. There is a good mix of small scale adventures and grand sweeping world saving quests. 

My world doc and background info is like 75 pages worth of stuff between histories, city descriptions, important NPCs, ect. My world is a combination/ inspired by Avatar the last airbender, a little Critical Role, some LOTR inspiration, and in some ways the witcher.

The only really big change I've ever made to the lore is getting rid of fixed alignments for most creatures with an intelligence score higher than three.  Certain creatures are basically always hostile (ghouls, fiends, many aberrations, a fair number of elementals) but nobody is surprised to see a gnoll walking down the street in a major city, going about his business, or an orc painter, or a hobgoblin teamster.  There are plenty of hostile orcs, gnolls, and hobgoblins, but nobody expects one to be dangerous any more than they expect a random elf, dwarf, or dragonborn to be.

My world is an alternate version of earth, called Tyllus, on which an alternate version of the Roman Empire still holds sway.

Custom-wise... I renamed all the playable races:

• Humans come in the variants Hill Folk (Romans), Desert Folk (Africans) and River folk (Egyptians)
• Elves are Light (High), Sylvan (Wood) and Grey (Moon).
• Dwarves are Ore (Mountain) and Bluff (Hill).
• Gnomes are Timber (Forest) and Shale (Rock).
• And so forth

My world is called Wyndalor, and has 5 major continents, with most of my campaigns set in the continent of Stormwyn. Huge kingdoms and great kings dominate this largely political landscape, and adventurers have trouble not getting rolled up in some elaborate plot. To the north east, there is the Börd. An icy wasteland where many mountain dwarves and goliaths reside. Beyond that sits the Styrmir, storm giant King Elgrvar's land. In the center of Stormwyn there is the Kelfer Dominion. This is the largest and most powerful kingdom, and determined to spread the church of Kelfer to all of Wyndalor. To the south lies Granhall, a kingdom of halflings and men. Their main export is grain and much of the kingdom is made up of farmland. They are considered to be weak on the political landscape, often staying out of wars or loosely allying with the winning side. But no lands can compare to the Shining City. Acriseon. Ruled by a Solar of immense power, this one city acts as an empire. When the god of life and prosperity, Falisfier, disappeared without a trace it's angels had no master. The one Solar among them, a powerful being named Acrison, took initiative and banded the angels together, using them as a sort of council and founded the city of Acriseon. Now it stands as a beacon of light and hope. If you want a better life, you move to Acriseon. 

However, things are changing. The powerful drow are leaving their dark nests and are launching attacks on Styrmir and King Elgrvar himself. War is brewing, and kingdoms are finding out where they stand. With Styrmir, doomed to fail. Or with the drow, who might after Styrmir begin taking other lands. 

Quote from Damian_Magecraft >>

The Realms (I have not really found a name for the world that seems to fit better as yet)

 Not bad.

Here's some more lore on my world, Axeoth. At some point in the Earth's future, the Demons of Chaos lead by a human who's name has been forgotten, invaded Earth. The nations of Earth fought valiantly, but it's leaders cared more for personal power and spent as much time fighting eachother. Thus was Earth destroyed, but hope not lost. Right before Earth was destroyed, the last humans and gods of Earth were rescued by an enigmatic race of creatures called the Old Ones who explained the true hidden origins of Chaos. The Old Ones also explained that Earth has put up the greatest resistance Chaos had ever seen, thus in order to defeat Chaos, Earth had to be reborn stronger. The Old Ones and survivng Earth life traveled for many years in space, until they found a frozen planet which seemed like a fitting place to create a reborn Earth. The Old Ones moved the planet closer to it's sun, and terraformed it to resemble Earth using DNA samples of all of Earth's plant and animal life. Then, the Old One tasked a chosen group of surviving humans to become the Gods of the world, and transformed them into gods. Survivng gods of Earth were allowed to continue their activities on this new Earth, and sentient life soon came, lizardmen, elves, dwarves, humans, etc. But Chaos soon found the world and was eventually able to invade it again. But this time, they were defeated. But this is not the end. Chaos has continued to threaten Axeoth, and though it has never succeeded in conquering Axeoth, Axeoth has never succeeded in defeating Chaos once and for all.

Ooh I like this thread! I wish some of these worlds were in print! Haha. 
My world is set on an infinite, flat plain. The sun and moon are in fixed positions opposite each other and it only works because of quantum shenanigans and physics being fundamentally broken. (You can go underground infinitely and can go into the sky infinitely and pressure and gravity are unchanging and this is fine) It was created within a simulation by two extremely powerful beings what exist one "tier" up in reality (where earth exists), and is run by a pantheon of "lower gods" (because the clerics and paladins and warlocks need them). 

The continent containing the adventure is an archipelago consisting of many many tiny islands and a couple mini-continents. It was settled 800 years ago by a massive pirate armada that got sent into exile into an ocean previously thought infinitely empty. It's a very "Pirates-of-the-Carribean", has controversial slave-labor via necromancy (skeletons make very nice cheap dock-workers) is embroiled in a massive divine civil war between the two Creator gods and a Rival god, and is on the verge of a technomagical revolution. I like it a lot. The end-game of the campaign is to stop a world-hopping madman that wants to kill all three of the big gods by ascending into the next tier of reality, which would plunge a literally infinite amount of people into chaos and death as a side-effect, but getting to that boss fight is a long time coming.