New Mewni

Mewni is an alternate dimension and the birthplace of Star Butterfly. It is a medieval land divided into several kingdoms ruled by kings and queens of various species. The most notable kingdom is Butterfly Castle, once ruled by King River Butterfly and Queen Moon Butterfly and currently ruled by Queen Eclipsa Butterfly. Their daughter Star was the former heir to the throne before a conspiracy was discovered of the true heirs of the kingdom.

Appearance
Mewni looks 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 is 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.

Locations

 * Butterfly Castle: The castle of the royal family.
 * Tapestry Room: A room in where the previous queens of Mewni are depicted in tapestry. Star calls it the "Grandma Room".
 * 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".
 * Forest of Certain Death: A dangerous forest occupied by carnivorous plants and monsters, seen in "Diaz Family Vacation".
 * Hydra's Lair: The lair of the Hydra.
 * Castle Avarius II: A dilapidated house that Ludo's parents moved into after he took control of their castle, seen in "Face the Music".
 * Unnamed village: A village near the Butterfly Castle.
 * Marketplace: A common marketplace found within the village.
 * 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.
 * Corn mine: An underground mine that Ludo used to make monsters grind corn for him. After Ludo abandons it, a group of "alternative monsters" moves in sometime before "Raid the Cave".
 * Monster Temple: Ludo's new home in the mountains that he and his rats, eagle, and spider moved into sometime after "Is Mystery". Destroyed in "Starcrushed". In "Monster Bash", it is revealed to be where Eclipsa Butterfly and her monster husband lived and raised their daughter, Meteora.
 * 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.
 * 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.

Role in the series
(In progress...)