Flintheart Glomgold is Scrooge McDuck's arch-nemesis and business rival, primarily because Glomgold is jealous of Scrooge's wealth and desperately wants to steal the title of "World's Richest Duck" from Scrooge, but so far has only managed to maintain his status as "World's Second Richest Duck" (though that title is somewhat in dispute with another of Scrooge's adversaries, John D. Rockerduck).
Under Carl Barks' authorship, Glomgold hailed from South Africa, where he made his fortune in diamond-mining. However, when he made his animated debut in the TV series DuckTales (1987-90), the U.S. government had tensions with the Republic of South Africa. Wishing to avoid controversy, as South Africa had been associated with apartheid and not with diamonds at that time, the Disney animators changed Glomgold's nationality from South African to Scottish. Another departure from the comics was that Glomgold is also just as notoriously stingy as Scrooge, but even more so, whereas Scrooge will at least be generous with his money on occasion. The animated Glomgold was shown as a big spender. This may have been an amalgamation of another one of Scrooge's rivals, Rockerduck, who didn't appear in DuckTales.
Selfish, dishonest and incredibly greedy, his goal is to become the world's richest duck, but the thing that makes him such a cruel duck is the fact that he'll cross every line to achieve this. Even to the point where he might even try to murder Scrooge. He cares for no one other than himself, acting as a loner at some points.
In the comics, Glomgold wears an ascot and black coat. This shows how different Flintheart really is from Scrooge. Unlike Scrooge, who does not believe in obtaining money through dishonest methods, which has resulted in him having many loved ones, Flintheart makes immoral decisions, which has resulted in him not having any emotional ties to any possible friends or family members. In DuckTales, he wears a kilt, tartan and tam o'shanter.
In the comics, he owns a money bin that mirrors Scrooge's. However, it is in the middle of a South African jungle as opposed to Scrooge's which is in the center of Duckburg. While Scrooge's money bin is almost all cash, Glomgold's is a mix of cash and precious gems, particularly diamonds.
Glomgold serves as one of the main antagonists of the series, making recurring appearances. As in the comics, Glomgold tries his best to become the world's richest duck.
He makes his series debut in the second part of the pilot movie "Treasure of the Golden Suns", in which Scrooge and his nephews find a map to a sunken treasure. Glomgold teams up with a villain named El Capitan to stop Scrooge and gain the treasure for themselves.
He would go on to scheme and battle Scrooge in several episodes. Some of his evil deeds include framing Scrooge for theft and having him arrested, banishing Scrooge to a remote island through the power of a genie and even having Scrooge's own employees work for him. He was also given John D. Rockerduck's habit of eating his hat when defeated by Scrooge.
Glomgold made brief appearances in both of the NES DuckTales video games.
At the end of the first game, after Scrooge defeats Dracula Duck, Glomgold shows up, being airlifted by a vulture (presumably a transformed Magica De Spell), and Scrooge must climb a rope up to the five treasures in order to win the game. If Glomgold reaches the treasures first, the player loses a life and has to fight Dracula Duck again. The HD remake, DuckTales Remastered, appears to expand on Glomgold's role in the game, adding in a sub-boss fight against him midway through the Himalayas level. It's also later revealed that he is the main antagonist alongside Magica. He and Magica teamed up sometime prior to the events of the game and manipulate Scrooge into collecting the five treasures so Magica could use them to summon Dracula Duck.
In DuckTales 2, after Scrooge finds all of the treasures, Glomgold takes Webby hostage and holds her for ransom on the pirate ship in the Bermuda Triangle. Scrooge gives Glomgold the treasures, only to discover that this "Glomgold" is actually a shape-shifting robot called the D-1000, programmed to destroy him. After the D-1000 is defeated, the real Glomgold sinks the ship and tries to take Scrooge and the treasures with it.
- Brian George, Glomgold's voice actor in DuckTales Remastered, previously voiced another Scottish villain in a Disney show - Duff Killigan from Kim Possible.
- Flintheart Glomgold made the Forbes Fictional 15 list of 2012 as #2 on the list although Scrooge didn't make the list that year.
- Glomgold is one of five characters in the Disney company to make the Forbes Fictional 15 list, with the others being Scrooge, Oliver Warbucks, Cruella De Vil, and Tony Stark (who's now a Disney character after Disney bought and acquired Marvel).
- He is briefly mentioned by Friar Tuck when the Sheriff of Nottingham is taking Otto's money.
- He is the second richest duck in Duckburg.
- His rival, Scrooge, is number one.