Setting
Though Stardew Valley has no set plot or lore, some description of the world can be found in various item descriptions, dialogue options, and Lost Books donated to the Museum.
Races
Humans
Dwarves
Shadow People
There are also Fairies, Junimos, Elves, Goblins, and Merpeople.
Humans
Humans make up the majority of Stardew Valley's population. Most humans live normal lives, however Wizards and Witches still exist and study ancient arcane energies.
Dwarves
Dwarves call themselves 'Smoluanu', or 'Sky People'. They are known for living underground and once having advanced technology in ancient times. Archaeologist M. Jasper believes they are an alien race. One dwarf can be found living in the The Mines.
Shadow People
Shadow people are beings that cannot stand the light. They fought in the Elemental Wars when the Dwarves invaded their ancestral home deep underground. Krobus is a shadow person who can be found living in The Sewers. Most of the shadow people encountered in the game are monsters found in The Mines, known as Shadow Brutes and Shadow Shamans. Humans also call them Void Spirits.
Junimos
Keepers of the forest. They are spirits which live with the trees. Most of the Junimos can be found living in the Community Center. They have inspired the Junimo Kart video game.
Fairies
Not much is known about them, but they occasionally appear to bless your crops.
Elves
Nimble and skilled craftsmen. Apparently extinct as no one has ever found their bones. Not much is known about them.
Goblins
Not much is known about this race other from the Lost Book written by M. Jasper. A goblin (the Henchman) can be encountered guarding the Witch's Hut, who will only move after being given Void Mayonnaise, which is considered a delicacy by the Goblin race.
Merpeople
The Wizard makes a reference to their existence during the Dance of the Moonlight Jellies, but nothing else is known about them. Very rarely, a merperson might appear under the left-most pier at The Beach, and then swim south. They are purely cosmetic and cannot be caught by fishing.
Tundra Dwellers
Referenced by Linus at the Festival of Ice, when he says "Igloo-building's an art I picked up from the tundra dwellers who live beyond the frozen sea."
History
Timeline
The Elemental Wars
An event referenced by the Wizard. It was the war between the Dwarves and Shadow People. The Dwarves, having driven the Shadow People from their ancestral home, forced the Shadow People to resort to violence. The Elemental Wars have long been finished, and the Dwarves and Shadow People must now live in peace for the sake of the humans living around them.
Now
After triggering the event telling about Community Center or talking to Morris you will have an important choice to do. "Now" is just a short period of time between "Past" and "Future", which means that this choice can change the future.
Geography
Stardew Valley Globe
Stardew Valley World Map
Stardew Valley
A peaceful region located on the southern coast of the Ferngill Republic. Dr. Harvey identifies its location over his shortwave radio as 52 north, 43.5 east.
Gem Sea
The ocean that makes up the entire southern coast of Pelican Town. There is a prairie-island located within it that had inspired the Journey of the Prairie King video game. Rumors suggest that Gunther comes from across the Gem Sea.
Fern Islands
An archipelago in the Gem Sea belonging to the Ferngill Republic. Willy is from there. When married to Haley, if at 13 out of 12 heart she will ask the player if they ever thought about retirement. Haley wishes to spend out your days together there.
Castle Village
It is unknown where exactly Castle Village is. It is known for its "artisanal velvet" as mentioned in the description of Earmuffs.
Zuzu City
This is the City where a number of people from Pelican Town are from. Haley apparently has visited it, as the Queen of Sauce mentions that she reportedly fell in love with her Pink Cake after visiting Zuzu City. Alex notes that they have a gridball team called the Zuzu City Tunnelers, and Shane will take the Player to a match for his 10-heart event.
Nations
Ferngill Republic
The nation in which Stardew Valley is located. Kent is a soldier for the Ferngill Republic, and is a survivor from a Gotoro prison camp. Morris believes that the Joja Corporation is good for the country as a whole.
Gotoro Empire
A nation at war with the Ferngill Republic. Located across the Gem Sea, south of Stardew Valley. The Traveling Cart contains goods smuggled out of the Gotoro Empire.
Religion
Yoba
Yoba is the creator deity. A shrine to Yoba is located in Pierre's General Store. Yoba is worshiped by both humans and shadow people.
Organizations & Factions
Joja Corporation
Adventurer's Guild
Wizards
Joja Corporation
A megacorp that seems to cover shipping, warehousing, distribution, mining activities, and energy drink production. The Player used to work for them. Morris is the manager of the local JojaMart, and Sam and Shane work at the local JojaMart unless the player completes the Community Center.
Adventurer's Guild
A place where adventurers gather to swap stories and sell their loot, the Adventurer's Guild is for those who have proven themselves courageous and strong. The Player is initially not a part of the guild, but upon entering the Mines for the first time, they are sent a letter the following day from Marlon, the leader of the Adventurer's Guild, who invites you into the guild if you slay 10 slimes. Upon entering, you are able to purchase swords, rings, and boots, as well as receive rewards from Gil, an old adventurer, for completing monster-slaying goals.