For an introduction to the duck comics, I'd suggest looking into the Carl Barks and Don Rosa collections put out by Fantagraphics. Those were very high quality.
Short version: Once, there was a man named Carl Barks, whose name, itself, sounds like a cartoon dog-man, but, in fact, was a comics writer. At some point, Disney gave him the directive to write funny Duck comics, and he took that as the excuse he needed to write the great American novel. In 1947, he introduced one Scrooge McDuck, and, from then until his retirement circa 1967, would go on to build a frankly absurd fictional universe, featuring numerous characters and concepts that live on to this day. Including:
Duckburg itself! Either a small-medium-sized town or a bustling metropolis depending on the story, Duckburg is, according to one of Barks' successors and his most prolific fanboy Don Rosa, located in Northern California, or, rather, in Calisota, a portmanteau of California and Minnesota, consisting of all of California north of the 39th Parallel. Don stated that , if one used a map, they could determine he placed Duckburg's specific location as "just across the bay from a very appropriately named real city". Given Don's sense of humor, this is probably Eureka(from the Greek "I Have Found It!"), California, which does fit with Duckburg's shown geography. Duckberg is populated by various anthro animals (Dogs, various birds including ducks, geese and chickens, and a few pigs, including the mayor). The most prominent landmark is Killmotor Hill (formerly known as Killmule Hill) in the center of town, atop which sits the famous Money Bin, which contains both Scrooge's office, and three cubic acres worth of money. There's also a prominent statue of town founder Cornelius Coot (more about him later) as another major landmark. Duckburg has an oddly-thriving space program, a sea port, several mountains (most prominently, "Old Demon Tooth"), a nearby "Black Forest", and, near Killmotor, the Tulebug River. It's also home to Yarvard University (ba-dum tish), the Billionaires Club whose members include Scrooge, Rockerduck and sometimes-Glomgold, and the Scrooge-owned Riz Hotel. Located near Duckburg is a farm owned and operated by Grandma Duck, a direct heir to Cornelius Coot and Donald's grandmother (on his father's side). She also employs Donald's cousin Gus Goose as a farmhand.
Woo! OK, but we're not done. Duckburg is the location, but Carl created a LOT of characters to fill it up. Starting with Uncle Scrooge himself. Everyone knows this guy. Industrialist, self-described "Adventure Capitalist", well known for his greed, vast sums of money, and unwillingness to part with same. Originally making his fortune in mining, he's since branched out to, uh, everything, basically, and, through that, became the richest duck in the world. He takes great pride in the fact that, despite his greed, he made his money "square". Scrooge used to be a much colder figure, but his time with his maternal nephew Donald, niece Della, and grand-nephews Huey, Dewey, and Louie has softened him. He's still a greedy old miser, but his friends and family are one of the few things that can match his pocketbook in his priorities.
Gladstone Gander! One of Donald's cousins, Gladstone is one lucky...Well, he's not a duck, he's a gander (IE male goose), but you get the idea. In contrast to Donald's bad luck, Gladstone is defined by his absurd, nigh-supernatural good luck. There was at least one occasion where he was hired to move a house from one hill to another, and a spontaneous hurricane appeared, picked up the house, and moved it as such, all without causing even the slightest scratch. That is...Pretty typical for him. He basically constantly trips over enormous sums of money, and, as such, has become incredibly lazy. Gladstone is about as lazy as it's possible for someone to be while still being able to move under his own power, putting in no effort of any kind at anything, knowing that his luck will give it to him in the end. He is also a smug, superior jerk. Quite possibly the only thing he exerts effort in is winning the affection of Daisy Duck, and he competes with Donald constantly for it...Ironically, that seems to be one of the few things his luck can't give him in the end (given that at least one story suggests his luck is the result of the goddess of fortune herself having a thing for him, this may make some sense). Another thing his luck can't get him is Scrooge's respect: Not that Scrooge really respects Donald either (they're generally pretty acrimonious), but he HATES Gladstone, his unwillingness to work for a living chafing against Scrooge's pride in his status as a self-made man. Not that Gladstone really minds. Worry is very much not something in his make up, including learning from his mistakes. While Gladstone can show a softer and even somewhat heroic side on occasion (such as when he caught a fleeing criminal by weaponizing his own luck, having a police officer promise a reward, resulting in the crook getting suddenly blown right into Gladstone's lap), in the end, he adores himself, and is content to wallow in the hedonism his luck allows for the rest of time.
The Beagle Boys! One of Scrooge's many antags, the Beagle Boys are a clan of identical criminals who have made many, MANY attempts to rob old Scrooge blind. They're crude, arrogant, greedy, selfish, and overall unpleasant. Perhaps their only redeeming quality is their sense of cameraide towards each other, although even this can get frayed. The Beagle Boys tend to be smarter then one would expect, many of them even possessing degrees in several disciplines, although they only ever use those skills for crime of course. They are also masters of trickery, and a vast arsenal of wacky weaponry, explosives, and gadgets. That said, they are not nearly as clever as they think, and tend to be, ironically, fairly gullible themselves. They usually don't have an official leader, acting as a unit, but occasionally do in the form of Blackheart (AKA Grandpa) Beagle, who first did battle with Scrooge as a younger man back in 1880, when a young McDuck was working on a Mississippi riverboat, and Blackheart and his three sons were starting up their crime ring. The current generation of Beagle Boys are the third gen. They've been to prison on SEVERAL occasions, but none of them have stuck. They also have worked with Scrooge's various other antags a couple times.
The Junior Woodchucks! This little org (and their sister organization for girls, the Littlest Chickadees) are a continual parody of the Boy Scouts of America. Huey, Dewey, and Louie are devoted members. They are notable for ostentatious titles (the triplets are Ten-Star Generals), awarding buckets of badges, very strict standards of behavior, and the Junior Woodchucks' Guidebook, a small paperback containing detailed and pertinent information on...EVERYTHING. No, really, EVERYTHING. It's basically the physical embodiment of exposition. How can a small paperback hold all that info? Well, that's covered in Appendix 137Q. Naturally.
Gyro Gearloose! Speaking of plot devices. Gyro is a chicken and is Duckburg's greatest inventor, a good-natured sort able to build just about anything...Although he often forgets about such things as "safety features" in his haste. He is assisted by his little robot helper....Little Helper, as well as his thinking cap, which is home to several birds. If the birds ever leave, it no longer works. Yeah. He has several relatives, like his grandfather Ratchet Gearloose who also met Scrooge back in his riverboat days, and his father Fulton Gearloose, who helped found the Junior Woodchucks, and invented the first ever Junior Woodchucks merit badge, then subsequently RECEIVED said merit badge to honor his accomplishment in having invented it. Gyro also has an ongoing rivalry with Emill Eagle, Duckburg's other resident inventor who is far less well-intentioned then he, and has caused trouble for Donald and friends on several occasions. He also used to be a star baseball player, with his his "madball" pitch — actually only a straight-ball pitch. Unfortunately, he ended up pitching his new invention, an unhittable baseball, against his other invention, an unmissable bat, with....Odd results.
Cornelius Coot. Said we'd get back to him. Born in 1790 to the Coot clan, a family who had been in America since Jamestown, Cornelius was the first of them to be historically notable, as he took up a job as a fur trader, moving all the way from the east coast to the west selling his wares. In 1818, he would arrive at Fort Drake Borough, a British military base in their colony of Calisota. While he was there, the colony was attacked by Spainish tropes from the neighboring California (Keep in mind that Calisota is what would be northern California in our universe). He made a deal with the small British garrison: He would gain control over the Fort for himself, claiming it for the US, but would still have to deal with the invading Spanish on his own. Fortuanley, he used an invention of his, popcorn, to trick the Spanish into thinking he had a massive army, and they fled. He renamed the Fort from Drake Borough to Duckburg, and established it as a fur trading port. He started a family, and continued to lead the settlement as it grew. Pretty soon, the village of Duckburg was flourishing. Even when they got annexed by a newly-independent Mexico in 1821, they managed to remain effectively a pseudo-autonomous city state, with their own laws, their own leaders, and, on the gripping hand, their own military, the Woodchuck Militia, a force that would guard the territory from any threat, including any conflicts with the Native Americans of the area. The fort that had once been the center of the area was now the Militia base, he spruced it up and built an extensive tunnel network to allow the Militia to move in and out even in a siege. In the process, he stumbled upon the body of Fenton Penworthy, the guy who had originally founded the fort back in 1579, and found a guidebook he had been guarding, passed down since Rome, that was said to contain all knowledge (Sound familiar?). Cornelius would become the next Guardian in line. After establishing a means of pumping mountain water into the town, he continued to lead them ablely, and proved to be a skilled diplomat, establishing peace with the local natives, and, according to certain (non-canon) sources, even ending up falling in love with and marrying one, Pluckahontas, sealing the peace treaty. They had a son, Clinton Coot, in 1830. Cornelius continued to act as Duckburg's de facto, if not de jure, leader for the rest of his life, even after Calisota got annexed into the US alongside California in 1848. Cornelius would ultimately pass away in 1880, at the ripe old age of 90 years old, and is remembered as the father of Duckburg. If you're curious, Clinton would go on to found the Junior Woodchucks, turn the guidebook his father had guarded into their guidebook, and eventually have a daughter, Elvira Coot, who would go on to marry into the Duck family, and become Donald's grandmother. Her son Quackmore Duck would be a man of a famously fierce temper, until the day he met Hortense McDuck, sister to Scrooge, the one woman whose rage could match his (she once fought off the Rough Riders with a broom). It was love at first fight, and they would give birth to Donald and Della Duck, the latter of whom would later marry
MADE YOU LOOK and have Huey, Dewey, and Louie. Scrooge's other sister, Matilda McDuck, is harder to track, but some stories suggest she ended up marrying Ludwig Von Drake, thus explaining how he fits into all this. So, yeah, that's how that happened.
FLINTHEART GLOMGOLD! This guy we've seen in Quest, but who is he? Flintheart is Scrooge's dark mirror. A Pekin Duck of South African descent (He's a Boer, specifically), Glomgold possess many of Scrooge's traits - his greed, his drive, his cunning and inventive mind, even his background in mining, for diamonds in Glomgold's case - but lacks any of Scrooge's occasional flashes of compassion and generosity. He is an unrepentant miser, tycoon, plutocrat, and all around bad guy, a being of untempered avarice who has no problem with lying, cheating, or using any other unfair tactic to get a quick buck. Glomgold is the Second-Richest Duck, and, though similar to Scrooge, even having his own money bin, its location is notable: Whereas Scrooge's is in the middle of the bustling city of Duckburg, Glomgold set up his in the valley of Limpaloo, South Africa, surrounded by wilderness in all directions. This in many ways is symbolic of Glomgold's real difference from Scrooge. Scrooge surrounds himself with family in Clan McDuck, the Duck family, and the Coot Kin, he has a vast network of allies and rivals both. Glomgold lives a life of solitude. He has no family, friends, or even rivals aside from Scrooge himself. While Scrooge has his nephews to help and advise him, Glomgold faces the world alone at every turn, and, while this has hardened him and made him much more ruthless than Scrooge, it has frequently led to him being defeated via simply being outnumbered. Regardless, Glomgold, despite his insecurities, is a ruthless schemer. There's a reason he's considered one of Scrooge's greatest adversaries.
John D. Rockerduck. This guy's actually pretty obscure in America, but he's BIG in the foreign markets, particularly Italy, which, as you'll see, is fitting. Rockerduck (an obvious Rockefeller parody), is, like his rival, a shrewd businessman at the head of a vast financial empire. Unlike both Scrooge and Glomgold, though, he is a liberal spender rather then a tightwad. Not exactly a spendthrift either mind, but he's much more open to the idea of spending money to make money, and loves to live a luxurious life and show off his riches, whereas Scrooge will often go to comical legenths in his determination to not waste a single dollar. Also unlike Scrooge, Rockerduck's empire is not his own: He's a scion of inherited wealth, and his father, Howard Rockerduck, a fact which both Scrooge and Glomgold are shown to resent as self-made men. He has few close friends, aside from Jeeves, his secretary, advisor, and right-hand man. Like Glomgold, Rockerduck is extremely competitive, determined to become the richest (or, at least, Second-Richest) duck in the world. He is an influential member of Duckburg's BIllionaire's Club. Another key distinction from Scrooge is the area of their investments: Whereas Scrooge is a proud Scotsman by birth, Rockerduck was born and lives in merry old England, and is generally more active in the European market then the American one (with attempts by Scrooge to expand his business abroad frequently running into trouble with Rockerduck). Rockerduck is also a passionate collector of many things (stamps, coins, art, artifacts), and is less morally scrupulous then Scrooge, often willing to resort to corporate espionage, sabotage, and even more severe acts like abduction, hijacking, or blackmail, although he usually outsources these to either the aforementioned Jeeves or, on several occasions, the Beagle Boys. Scrooge and Rockerduck despise each other, but Rockerduck does find him a worthy foe and there's a certain mutual respect there. On several occasions, the two have even teamed up for a common goal, although never for long. Turns out Rockerduck can be remarkably pleasant company, particularly if you aren't Scrooge. This, needless to say, is a major difference from Glomgold.
Magica De Spell. Another face we've seen in the Quest. She is a witch, living on the slopes of Mount Vesuvius near Naples, Italy. Her goal in life is to claim Scrooge's Number 1 Dime, the first piece of money he ever earned, which, as the first piece of money the world's richest duck ever owned, has enormous symbolic and, thus, magical value. It is said that, if it is burned in the fires of Mount Vesuvius and then a ritual performed, it will become an amulet that grants the wearer the Midas Touch, the power to turn things into gold. She's worked with the Beagle Boys in the past to get that dime, but actually has her own network of associates, like the raven Ratface or her apprentice, the no-talent bungler Samson Hex. She also has an...Oddly vast family, including her grandmother Granny De Spell, said to be an even more powerful witch and one of the strongest spellcasters in the world...Not that she was able to do any better when she tried to steal the Dime, her sister the Wicked Witch of the West, the Wicked Witch's mischievous daughter and son, Witch Child and Warlock, who Magica is sometimes forced to babysit to her chagrin, another niece called Minima De Spell, and a cousin named Witch Matilda, who once apprenticed under Magica. There's also Rosolio, a dim-witted goose who claims to be Magica's fiancé despite constantly being rejected. He is supported in this effort by a different grandmother, Caraldina. Magica has an odd relationship with Scrooge. Occasionally, they have been able to meet on somewhat amicable terms. A few stories have even implied pseudo-romantic feelings on either end, but, for the most part, she is a potent enemy who has besotted him and his family for years.
WOO! OK, there's many more characters to cover, but i'm hoping to finish this sometime before Jewish New Year, so....That's where i'm cutting it off. But, if you ever wanted to know the Duck Lore (Woo-hoo! Sorry, instinct), now ya know.