Old MewniAt first, Mewni looked like a typical fairy tale locale, with various magical creatures and a royal family. Families of nobility include the Butterfly family, the Pony Head family, and the Johansen family. As seen in "Diaz Family Vacation", the occupants residing in Mewni and their place of residence appears to depend on their status in the hierarchy: peasants occupy the lowest land (bottom level), having dirty streets and widespread poverty; then presumably middle-ranking residents occupy the middle section (second level), which is less atrocious than the previous section; and the nobles occupy the highest part of the land where the castle is prominent (top level).
Beyond the Butterfly family's kingdom was a swampland, where Mewni's indigenous monster population were forced to flee after the first settlers forced them off of their land. Mewni's main crop is corn. Some of Mewni's fauna and flora are similar to Earth's, but others are mythical.
According to Star and Marco's Guide to Mastering Every Dimension, the royal lineage of the Butterfly family is "matrilineal", meaning the queen holds more authority than the king, and the throne is handed down from the queen to her firstborn daughter. As a result, King River Butterfly (born River Johansen) took his wife's last name upon their marriage.
Since Mewni merged with the many other dimensions in the SVTFOE lore, it's become a mix-matched land with each dimension's setting with mixed relationships. The dimensions formed a single world inside a dimensional capsule.
- New Monstertown: A Monster Temple that Ludo briefly made his new home when he was possessed by Toffee that was destroyed in "Starcrushed". In "Monster Bash", it is revealed to be where Eclipsa Butterfly and her monster husband lived and raised their daughter, Meteora. Since becoming queen, Eclipsa made this the new capital while Butterfly Castle has been abandoned.
- Butterfly Castle: The castle of the royal Butterfly family that has been abandoned since the attack of Meteora.
- Tapestry Room: A room in where the previous queens of Mewni are depicted in tapestry. Star calls it the "Grandma Room".
- Unnamed Village: A village near the Butterfly Castle. Since Butterfly Castle was abandoned, the village went into anarchy.
- Marketplace: A common marketplace found within the village.
- Castles: A pair of castles near to Butterfly Castle.
- Castle Avarius: The castle in which Ludo and his army previously dwelled. Used to belong to his family before he changed the locks while they were vacationing and took it for his own. Destroyed in "Storm the Castle" then rebuilt in "Princess Quasar Caterpillar and the Magic Bell".
- Forest of Certain Death: A dangerous forest occupied by carnivorous plants and monsters, seen in "Diaz Family Vacation".
- Castle Avarius II: A dilapidated house that Ludo's parents moved into after he took control of their castle, seen in "Face the Music".
- New M'onstraus: Once an entirely separate dimension founded to escape Mewman discrimination, and the brief living residence of Buff Frog and his adopted children, but due to it's closeness to the main Mewni Dimension, it was merged alongside the rest to become an entirely monster exclsuive land within fair distance from New Monstertown. It is ruled by Toffee's more moral cousin Taffee.
- Rat Bar: A small bar for rats to socially interact and eat porridge.
- Buff Frog's House: The house where Buff Frog lives with his adopted tadpole children.
- Sanctuary: A magic sanctuary/hiding place for the Butterfly family and Magic High Commission.
- Johansen Kingdom: The kingdom of the Johansens, King Butterfly's born family. Located to the east of Butterfly Castle.
- Pigeon Kingdom: The kingdom of the pigeons. Located to the west of Butterfly Castle.
- Jaggy Mountains: The kingdom of the Jaggy royal family.
- Forest of Unlikely Spider Bites: The kingdom of the Spiderbite royal family.
- Underworld: A sub-level kingdom located deep in the Mewni underground. Ruled by the Lucitors, Tom's family.
- Lava Lake Beach: A beach with an ocean of lava and the location of an annual Soulrise.
- Cloud Kingdom of the Pony Heads: A kingdom that spans Mewni's entire sky, just below outer space. Ruled by the Pony Heads, Pony Head's family.
- Kingdom of the Waterfolk: An undersea kingdom that encompasses all of Mewni's oceans. Ruled by the Waterfolk.
- Lake of Endless Suffering
- Dam of Constant Sorrow
- Bridge of the Inevitable Hereafter
- Village of Monsters: A small village in Mewni where a community of monsters resides.
- Pie Island: A volcanic island ruled by the Pie King and the ancestral home of Star's family. The Pie folk are renowned con artists that scam anyone.
- Echo Creek: A town in Los Angeles, the birth city of Marco, and the foreign home of Star.
- Echo Creek Academy: The high school where Star and Marco attended.
- The Diaz Household: Rafael Diaz, Angie Diaz, Marco Diaz, and Mariposa Diaz's home and Star's home when she lived on Earth.
- Hill-Trank Plaza: A small strip mall where Sensei Brantley's dojo is located.
- Britta's Tacos: A fast food restaurant that sells Mexican food and the location of a well entrance to the Realm of Magic.
- Amethyst Arcade: A cavernous arcade location full of literal 'squares'.
- The Scum Bucket: A dance club in an underwater dimension. Its patrons commonly consist of sharks, dolphins, and merpeople.
- Woolia: The home dimension of Kelly full of people with massive wooly hair and like to punch each other as payment.
- Neverzone: A dimension with a time dilation that causes a year to pass by every 30 seconds, causing outsiders to age mentally and physically rapidly. Since merging, the Neverzone has become a dead valley where the time dilation exists as a land-spanning anomaly.
- K.I.T.T.E.N.S.' base: A Nowhere Gas Station that was momentarly turned into the HQ of the Pie King's briefly lived coup of conspiractors trying to capture the Mana Star to bring magic back for only them to control it. Apawn capture of the Mana Star, it was converted into becoming a castle made of pastries, and was surrounded by a legion of Pie Knights, only for it to face destruction by sweets-hungry monsters and Star beating Pie King, who self proclaim himself as the Pie Emperor, frees the Mana Star and takes back the royal wand, whilest Eclipsa declares Pie King to be exiled back to Pie Island and is banished from the rest of New Mewni for his actions.
- St. Olga's Reform School for Wayward Princesses: A former reform school that unethically turned carefree princesses like Star into the same brainwashed state of being a perfect princess, and even if they learned of his true gender, the princesses there look up to Marco as 'Princess Turdina' for helping save them from it's former headmistress Miss Heinous, who is also Eclipsa's half-monster daughter Meteora. The school is now a wayward princess party club with no rules.
- Pixtopia: A largely wooded world inhabited by pixies and ruled by the Pixie Empress. It's been known for it's Shard Mines, where magic mirror users are forced to work off their overdue bills, which was eventually shut down non-canonly for it's illegal slavery alongside the magic mirror service.
- Mewkatraz: A secret prison for war criminals on both Mewman and Monster sides. It had to be placed under a new rulership due to the previous Head Warden's incompidence.
- Steampunk Pirate Island- An island of steampunk pirates. Though the Pirate Dimension was usually far off from the Mewni dimensional range, because of Star's influence, the island ended up being adopted and was put in the New Mewni ocean as now Star's old steampunk pirate friends rule the seas. Though in the process the adoption of the island accidently brought over a collection of Skull Pirates lead by the Pirate Skull King's best LT: Boner Fjord. He has been attempting to bring his master and the other Skull Pirates into New Mewni ever since.
- Pirate Island- A normal island nearby both Steampunk Pirate Island and the Skull Base where rabbit pirate acquaintances of Star live. Since New Mewni formed, this island shares the same archipelago as Steampunk Pirate Island.
- Asper Island- Something that was apart of Old Mewni, but apawn the merge it drasticly moved the island in a furhter location that upsetted the island's volcano and caused it to sink into the sea. Prior to this, the island was both home to the native Isleraptorians and several exclusive fauna and flora spieces before the merge forced them to evacuate the island while taking all animals and seeds of the native plants to have a new home in one of the islands untouched by the resident pirate dimension pirates and recolonised, and that it also was the unfortunate site of it being the base of manufactoring war machines of Asper's design as it was also his private island where he constructed the Fleshborgs, which included Gemini, in being meant to repalce the Solarian Program until Asper's Exile forced him and his loyalists to abandon the Flesh Borgs on the island base, where it even was the island where Olga was made when he bought her from the Roboloid Dimension. The Island is now underwater in the deepest deaphs impossable for even the most advanced submarines to reach, foreevr concealing a part of the worse of Asper's legacy for good, which to some, is better that way.
- Bloodfall Valley- A bizarre land inhabited by living blood cells, parasites, and hemophages. First enountered by the Shell Lodge when Lord Millipede caused trouble, this former part of another dimension ended up here as an adoption because of a minor enough influence even when Star didn't get to interact with the place much. It is now home to the crew of Captain Leechsuck, who despite being discouraged by his predicerment, came to befriend Star and even helped settle the dispute between blood-sucking monster species and Mewmans, which helped that the Blood Falls are next to New M'onstraus. Leechsuck momentarily suffered homesickness until magic was restored and Star gave him dimensional scissors that allowed him to visit the Disembodied Heart Dimension when he pleased. The downside is that it also brought over an endless parasite hive as now the parasitic beasts are an invasive spieces in New Mewni, but are kept in check by Chaemera in absence of the Golden Hearts.
- Goldtown- The hometown of Stingzy and her mentor Rusted Belt, who moved back with his crippled granddaughter after Lord Millipede's incident lead to Belt rekindling with Stingzy. Because of Star's influence, the town ended up adopted and has now appeared in the distent desert next to New M'onstraus, of which the town is now a favorite to greed-sensitive monsters and wealth-lovers alike. The town still keeps in touch with the Endless Gold Rush Dimension. The only flaw is that now the dimension's outlaws come into New Mewni as well due to newer pastures and opportunities to roam, but thankfully Star and friends proved a discouraging challenge.
- Cactica- A home of cactus people which has it's own kingdom with a princess named Princess Thorne, one of the former students of St. Olga's who looks up to Marco as Princess Turdina.
The Dimensional Wastes
- The Mansion of Dimensions/Millapede's Mansion- An entire interdimensional freeway now a regular freeway. In an interesting case, Millapede's mansion, once a place found inbetween dimentional realms, has found itself now part of New Mewni as a remodeled gateway to other realms. The Mansion was renamed the Mansion of Dimentions and was turned into a dimentional embessy for every living thing of the Multiverse. It even subsiquintly became Millapede's new home in New Mewni after he was pardoned for his risk factor, even seeing the return of his former famegafairy servents under parole.
- Relic Land- A land and former interdimensional tourist attraction full of the strangest relics from all over the multiverse where Star once took a school field trip and saved it from 'the universe's most deadliest creature', a sentient yarn thread.
The Church of Love
- St. Lovers- The same church from the Romance Dimention where Millipede's wedding with Sunset Shimmer took place, now having been adopted by the Mewni Dimentions and becoming a shorce of impourent reminders of love, which was espiecally needed to ease away the enfluence of Asper. It did became a shorce of over-excited mushy love concerts though, to the distain of cromugens like Ludo's father, who's made to come here by Ludo's mother.
- Gamble City- A city with Cuphead-like inhabitants bigger than Las Vegas.
- Raider's Market- Once a viberent place where Verse Raiders sell mortal slaves. But it was discontinued apawn the city it was in being adopted by a remerged New Mewni and how the city now has to follow new rules.
- Jackpot Paradise- The casino and devient Outer Go traveling place home of the goodhearted Chancespawn Jackpot, along side being the retirement home of the Magic Commission Members apawn being replaced by the newly dubbed Magic Commision Members in Star's Outer God friends, who came to gotten smitten by some of the residence, Hekapoo falling for Jackpot, Omnitraxus caming to have a greater bond with a former Time Counciler, and even Rhombulus coming to become a closer "special friend" to a chitterly hyper-active defect female bladebra. Jackpot is Star's go to guy to get a head's up on the latest issue about Outer God politics, so to be better prepared against either rogues or other cosmic surprise.
- Queen of the Willtopians Palace- For a mysterious reason, the Mewni Dimensions adopted the entire Willtopian Palace and turned it into a giant dark skied island at the farthest distence from New Mewni. Though it was suggested that it is because the re-combined realms figured that the Willtos needed to be watched over and to see if their misguided yet parasiticly loving ways can be mended.
Role in the series
After two previous episodes, New Mewni is a new world in The United Universes. The Mewmans are revealed to have been interdimensional immigrants whose original home dimension was destroyed by an outerdimensional monster called The Xexaxez, which are bred by The Amoral Ones to prevent interdimensional imbalance through dimensions that have grown too powerful to the point of adapting and damaging other dimensions, sending Xexaxezes to exterminate them. Their original dimension of Mew was one of these rogue dimensions and they went to Mewni, resulting in their conflict with the native monster population and the events of Mewnipendence Day in which the Great Monster Massacre brought the extinction of several monster races. Though as time passed, Mewmans forgot their true origin and some of their royalty tried to make up for their sins including Eclipsa and her monster husband, until their crystallization left the Magic High Commission to not only lie about her hybrid monster daughter, but also mistakably label and judge other monsters by threat levels alone, ignoring other crucial details in the process. It's also later revealed that the monsters of Mewni are actually from the Bestiary Dimension, the same dimension that spawned the world of Amphibia, and Mewni was just a colony founded long before the arrival of Mewmans as the result of their dimension's native leader turning in rogues who almost used magic to establish an interdimensional empire into the Outer Gods and sending away the rogues' families to other dimensions to keep history from repeating itself, sending King and Queen Varlet to 'M'onstraus' because their own parents were the worst influencers. With this revelation giving the realization that Mewni never belonged to either side and bringing in a war about who should keep it, Glossaryck is forced to reveal that New Mewni was originally an 'orbital multiverse', a collection of universes that orbit each other, and seeing this orbital multiverse as the purest to where it felt like they loved each other wishing to unite into one, he and the Magic High Commission gave it a trial to not only help prove that Outer Gods and mortals need each other through amoral acts that would guarantee mistrust, as well as create a 0-Bravery Mortal, a mortal who can stand up to Outer Gods no matter how powerful they are, but have it earn a unification once it created an extremely powerful bond, which turned out to be Star Butterfly and Marco Diaz when they were willing to sacrifice themselves in each other's arms in a dying Realm of Magic, not wishing to leave each other saying they belong together with or without magic. This bond earned New Mewni it's existence.