Big Screwed-Up Family: Åland can be a real jerk to his cousin, Finland. As for Scania and Fenno-Swede, the author says, "All the children in SatW are completely fucked."
Norse By Norsewest: Mainly averted. The comic shows the countries' stereotypes of each other rather than the Hollywood stereotype of them, and goes out the way to show that each country has their own distinct cultures.
Power Trio: Denmark as the Id, Norway the Ego and Sweden as the Superego.
Sitcom Archnemesis: With Sweden, though mostly in strips focusing on internal Nordic relations. Other times they're shown alongside each other (and Norway) with no apparent animosity, especially if they're representing Scandinavia as a whole and/or interacting with another part of the world.
Character Development: Sweden is the character who by far has changed the most since the beginning. He started off with his sexuality being only a subtle implication that was never spoken of and he always dodged about, but over time he slowly has been opening up, and eventually he acquired a boyfriend.
Sibling Yin-Yang: With his sister. One really has to wonder how they ended up so different.
Sitcom Archnemesis: With Denmark, though mostly in strips focusing on internal Nordic relations. Other times they're shown alongside each other (and Norway) with no apparent animosity, especially if they're representing Scandinavia as a whole and/or interacting with another part of the world.
Kissing Cousins/Fridge Horror: Norway introduced the others to his cousin Jan Mayen as his “friend”. Sweden commented that he looked dead. It was later revealed that Norway and Jan Mayen used to have an incestuous relationship, and that Jan Mayen got killed for it. That means Norway is keeping the corpse of his dead lover somewhere in his house...
The Quiet One: Humon originally wanted him to be medically mute, but later decided he's mute by choice. He'll really only swear, and talk if he has to. The most he ever says is (roughly) "Are you mocking my hat...?" and "You're mocking me..." in the strip where Humon has everyone talking in their native languages.
He's also not too crazy that he knows Swedish, or that his nephew speaks nothing but Swedish.
Sign Language: Sometimes he waves his arms around in his own bastardized version of this (before resorting to using literal signs) though Aland gave up on trying to understand after he used similar gestures for "Vodka!" and "There's a cat under the house!"
Talking with Signs: Sometimes resorts to this to communicate without speaking, though hilariously even his signs are often wordless pictograms.
Disappeared Dad: Subverted—Denmark is his father, though neither of them knows it. (When Sweden finds out, he tells Scania his father was killed in a car accident so that the boy wouldn't look up to the irresponsible Denmark as a role model.)
Cheerful Child: Despite his insane family. Apparently it's because his mother spoils him. note This is a reflection of the Finnish stereotype of Fenno-Swedes being annoyingly happy all the time.
The Voiceless: He doesn't speak very often. Most he's said to date are "Yes!" and "No sir!". He speaks Swedish (shown by the flag in his bubble) which pisses Finland off to no end. This is a reflection of real life Fenno-Swedes.
The Hermit: Of the "wilderness survivalist" variety.
Posthumous Character: Was apparently executed during the Renaissance for having an incestuous relationship with Norway, which is only revealed several strips after his first appearance. Sweden points out that "he looks dead". That's right, Norway introduces his friends to the dead body of his onetime lover/cousin. Which he keeps around to have conversations with. (In real life, Jan Mayen is an inhospitable volcanic island with no real population other than some researchers.)
Pity the Kidnapper: When Denmark had to give Bornholm up to Sweden, Bornholm responded by beating Sweden up until he let him go back.
Nephewism: Possibly this with Norway. The paternity with Fenno-Swede and Scania is the child having the father's language but within the mother's land. So Kven may be Finland and Sister Norway's child.
"Well, if you must ask; I'm an intellectual who speaks more than 20 languages, my food is excellent, my art is deep, I'm a great lover who is sexy without being vulgar, I rule my kingdom with peace, and I ride a mean scooter."
The Atoner: Has shades of this, out of guilt for Nazi Germany's actions.
Fridge Brilliance: The characterization of the different nations is related to national stereotypes. Germany has literally become a different person since World War II.
German media also constantly reminds its own population every day about the horrors Nazi Germany committed, through articles, documentaries or the history lessons in school. This also adds to the stereotype of them constantly apologizing for WWII even if they were not reminded of it by someone.
Butt Monkey: Denmark and Netherlands just won't stop targeting him with their bizarre sexual fetishes. To be specific, they aren't even interested in him; they just like to assault him in front of Sister Japan to provoke her yaoi-induced nosebleeds. Austria also seems to do this to him.
Sibling Yin-Yang: Sister France (the main sibling of the pair) seems to represent all the cultured, hip, and sophisticated aspects of French culture, while Brother France embodies the snobbery, pretentiousness, and rudeness.
Big Eater: America eats fattening food like it's nothing.
Dark-Skinned Blond: He starts turning into one when he realizes white people are becoming a minority in his country.
One comic showed him with light skin, despite the the change. Humon stated in the first comic he became dark-skinned his hair was blond because he bleaches it.
Eagleland: While America certainly has most of the Flavor 2 traits, he does genuinely want to help others and is seen as the peace keeper when things get too out of hand (if only because he's dumb muscle). Essentially he's a Type 2 who aspires to be Type 1. Generally a mixed flavor.
Zigzagged, actually. America likes to pretend he's really macho, yet he's actually the more sensitive of the two.
Strawman Political: America flip-flops between left and right depending on the comic. Though with Sister America getting more characterization, he might be staying to the right.
Humon has stated that the America siblings basically have the minds of teenagers, making them incredibly opinionated to the extreme, but completely unwilling to do any research whatsoever on anything they're talking about. Leading to "debates" on whether gays are penguins or flamingos, and whether it's right to step on their eggs.
Transparent Closet: Humon stated that America has a lot of repressed feelings for Canada, and is most likely doing some stuff "on the down-low".
When You Coming Home, Dad?: England was a rather inattentive parent to America. Now, any time America wants England's attention, he acts out. One such event was the Boston Tea Party.
Flanderization: Sister America started out as a Rich Bitch parody of shallow valley girls who are obsessed with plastic surgery, then she became a girl obsessed with sounding liberal without knowing anything about liberalism to balance out her brother's conservatism. Then she met Sister Japan and now she's mainly just a Yaoi Fan Girl.
She's seems to have backpedaled from this characterization in recent comics, though.