Protector of his kingdom and family, King Fergus is a heroic warrior with a majestic bear cape, broad sword, and a knobby peg leg – the result of his much-regaled skirmish with the demon bear, Mor'du.
Snippets of dialogue throughout the film reveal Fergus' history. Once only the leader of Clan Dunbroch, one of the four largest clans in the Highlands, Fergus took part in many of the inter-clan feuds and battles between his clan and the other three. When Scotland fell victim to the Northern Invaders (presumably Nordic warriors), it was Fergus who brought the four clans together to fight their common foe. Inspiring the people with his warrior skill and leadership abilities, when the invaders were driven off, the leaders of the other three clans bowed their heads to him and named him their High King.
At some point after this, Fergus entered into marriage with a noblewoman named Elinor, who bore him a daughter, Merida, and much later, triplet sons.
King Fergus is a loud, easygoing man. He is a very kind person and is very friendly, getting along with others quite well. He is the polar opposite of his wife in that he doesn't stick to or adhere to tradition as strictly as her and enjoys having fun with his children. He does have a temper, often getting annoyed at the antics of his triplet sons and the lords but he knows how to have a good time and can be fairly patient. He is fun loving and easy going, often playing around with his children rather than bringing them up to be royalty. In fact, he even states that he feels that a person needs to protect themselves and defended Merida's choice of using bows, seeing them as a valuable weapon for self-defense.
He has a good sense of humor which he passed on to Merida, such as when they both mock the lord's sons attempts at shooting arrows. He loves fighting and enjoyed getting into a brawl with the other lords and their clans. However, he is also a wise ruler and knows when to be serious. Though he entered into an arranged marriage with Elinor, he truly loves her as if they married for love and was so upset when he thought she died that he sent everyone including the lords and their clans to hunt down the bear responsible (not knowing that Elinor didn't die but in fact was the bear). This also coincides with his ability to hold grudges, as he held a long-standing grudge on Mor'du for eating his leg.
He treasures his daughter as well to the point he told the other lords that none of his sons were fit to marry his daughter. He seems skeptical about the idea of myths and doesn't believe in magic, as shown in the beginning when he makes fun of Merida for claiming she saw wisps and refused to believe her when Merida told him the bear he'd encountered in the tapestry room was his wife under a spell.
Overall, he is a kind loud exuberant ruler and father who is proud of his family and protective of them and his kingdom.
King Fergus is a heroic warrior with a majestic bear cape, broad sword, and a knobby peg leg – the result of his much-regaled skirmish with the demon bear, Mor’du. His vendetta against the beast who took his leg makes Fergus a ferocious and determined bear hunter, evidenced by a home full of mounted trophies of every size. Protector of his kingdom and family, Fergus has a heart as big as his triplet sons are mischievous and boundless love for his wife, Queen Elinor. But his pride for his first-born daughter Merida is unmatched, and he has gifted her his great skill and passion for the sword and the bow.
Fergus is first seen putting his bow on the table on the day of his daughter, Princess Merida's birthday. When his wife, Queen Elinor sees him putting his bow at the table, she tells him not to put it until Fergus presents Merida with her own bow as a birthday present. Fergus is later seen teaching Merida as Merida accidentally shoots her 6th arrow into the forest and goes to get it back while Elinor nervously watches the whole thing. Merida comes back and says she saw Will O' the Wisps. Elinor explains that the wisps lead people to their fate but, Fergus doesn't believe it. Suddenly, Mor'du attacks, and Elinor and Merida flee while Fergus stays behind to fight the demon bear with his royal guards. He initially tries to kill the demon bear with a spear, but after it bites the head clean off, draws his sword and goads it to attack. It is later revealed that the king's sword shattered against the bear's hide and, though he managed to survive the encounter, it cost him his left leg which possibly explains his strong hatred for bears.
Years later, Merida is a teenager that Elinor is trying to make into a proper princess despite Merida's objection; at one point, Fergus is trying to show his daughter how to tame a falcon, only to be attacked and mauled by both birds when Merida takes the hood off, much to her amusement. At night, after a free fun day, Merida listens to Fergus telling her triplet brothers the story of his battle with Mor'du until she interrupts and tells them that their father lost his left leg in the battle, and Mor'du is waiting his chance of revenge, which disappoints Fergus ("Oh! That's my favorite part!") but delights the triplets as they were bored stiff from having heard it all before to the point that one was able to accurately mimic Fergus' words and actions while telling the story.
Moments later, Elinor tells Merida that the three Lords are coming to present their suitors to compete for her hand in marriage. Not wanting any of this, Merida angrily storms out of the Great Hall to her bedroom. When King Fergus sees his three sons crawling out from under the table with some things hidden in their shirts (cakes and other desserts) and leaving, he tries to go after them until his peg leg, which has been tied to one of the legs of the table due to the mischief caused by the triplets, causes the whole table and everything on it to fall. Fergus is so furious about this that he shouts after them: "Boys!!!"
After Queen Elinor fails to talk to Merida about the story of a king who divided his kingdom for each of his four sons to rule but the eldest wanted to rule the entire land so he brought chaos and war that led to the downfall of his kingdom for following his own path and about going through the whole marriage thing, she is seen in the tapestry room sewing the family tapestry and talking to Fergus of what she would say to her daughter about her wishes if she would listen.
Days later, the Lords arrive in DunBroch and Elinor prepares Merida in a tight formal dress, tells her to smile, and they all gather in the Great Hall for the presentation of the suitors. Each of the Lords presents their sons, but their playful rivalries cannot stay suppressed and a brawl breaks out. Elinor is not as pleased as Merida is. King Fergus silences the brawl but it breaks out again due to the mischief caused by the triplets. Unable to resist a good fight, Fergus jumps right in and takes on all three lords at once. Elinor, not pleased with the event, grabs Fergus and the Lords by their ears, then proclaims that only the firstborn of the great leaders may compete in the games. When Merida declares that she chooses archery, it was time for the Highland Games to begin.
When the competition begins, Elinor tells the three suitors good luck. As each of the suitors shoots arrows, she tries to silence Fergus and Merida chatting about each of the suitors until Wee Dingwall wins by accident when Fergus startles him at just the right moment. Merida appears on the field; declaring she will shoot for her own hand; to Elinor's shock and Fergus' amazement. Ignoring Elinor's protests, she strikes the bullseye of the first two suitors' targets. When she shoots an arrow through the full length of Wee Dingwall's arrow and through the target, she smiles... until she sees her furious mother.
Later, at night, Fergus is seen talking to his men, the Lords, and their clans about his bear hunt adventures. When he sees Merida taking Elinor, who is now sick after eating the cursed tart, to her room, he asks her if Elinor is all right and she says yes and to let him continue whatever it is he is doing. A few moments later, Fergus hears a roar (Elinor in bear form now) in the castle and smells something strange: pointing that "something's not right." Then, he leads his men, the Lords, and their clans to a bear hunt around the castle. When he sees Maudie, the nursemaid running and screaming towards their way, he asks her what's wrong and she replies: "Bear!" which causes Fergus and the rest to charge and continue on hunting for the bear.
Eventually, they follow the "roar" and "shadow" of the bear (actually, part of the triplets' tricks as a way to help Merida and Elinor escape the castle) until they are led to the top of a tower. When they see no sign of their bounty, they decide to come back inside but the moment Fergus tries to open the doors, he finds out that they're locked, so, they're locked up outside the tower. A few moments later, he is seen climbing down from the tower with the rest of the men; using their kilts tied together to make a long rope, and walking half butt-naked back to the castle.
The next night, Fergus and the Lords are seen behind barricades, hurling weapons at each other, on the brink of war. Merida tries to tell Elinor to stop them. But Elinor, in bear form, can't do any such thing, and it is up to Merida to stop this madness. Elinor, fearful of being seen and attacked, freezes into a stationary position while Merida walks into the room and tells them she was in conference with Elinor. The Lords demand to see the queen until Merida silences them all. She tells them of the story of the selfish prince who brought chaos to the land and reminds them that legends are lessons and they ring with truths. The clans had been enemies until they were threatened by the Northern Invaders and joined forces to defend their lands. When they won the war, the clans made Fergus their king for bringing them together and made an alliance. Merida then tells them that they should be free to follow their hearts and find their own love. The Lords' sons agree with this and confess to their fathers that they didn't want to fight over a girl who doesn't want any of it. So they all agree, but Merida notices a guard staring at Elinor's frozen pose and distracts everyone by telling them to go to the cellar to celebrate. When everyone is gone, Elinor is proud of her and they both head to the tapestry room.
As Merida is looking for thread and needles to mend the tapestry, Elinor turns wild again and attacks Merida. When Fergus enters the room (after realizing that his wife is gone and her clothes torn off; thinking that she has been killed and eaten by Mor'du), she attacks him and cuts Merida's arm. When Elinor snaps out of it, Merida tries to calm her, but her mother flees in horror as Merida tries to tell Fergus that the bear is Elinor, but Fergus refuses to listen. He locks her in the tapestry room for protection and gives the key to Maudie while he and the Lords go after Elinor.
After having captured Elinor, Merida, who managed to escape with her brothers' (who have been turned into bear cubs for eating the rest of the cursed cake) help, interferes and fights Fergus to keep him from killing Elinor, until he is convinced when the three bear cubs help stop him and realizes they are his sons the minute Merida calls them "Boys".
Suddenly, the real Mor'du appears and attacks the soldiers and Fergus. When he attacks Merida, Elinor breaks free from the ropes and saves Merida just in time and starts fighting Mor'du. After slamming Elinor into one of the stones, he turns to kill Merida again until Elinor lures him into smashing again the now cracked stone, which then crushes him to his death. They notice a wisp coming from his body revealing the image of the prince; nodding thankfully for releasing him from his curse, and then disappears. Merida realizes it is the second sunrise and grabs the tapestry and throws it around Elinor but realizes nothing's happening. When Merida thinks she failed, she tearfully hugs her mother and apologizes for everything and that she loves her. Then, the tapestry magically seals and Merida feels a human hand touching her hair and realizes Elinor is human again. Elinor is so happy and proud that she kisses her daughter lots of times. Fergus comes to hug his wife and daughter and kisses Elinor. Merida reminds her that she is naked under the tapestry then Elinor tells Fergus the same thing, so, he tells the Lords to turn around as the triplets, turned back to humans too, come running naked and hugging their parents and sister.
Some time later, Fergus and his family are at the harbor saying goodbye to the Lords until he notices the triplets have stowed away on one of the Lords' ships; waving goodbye, thus, forcing an annoyed Fergus to ride on a boat to go after them and retrieve them.
Some time after the events of Brave, an army invades DunBroch from the south. Unsure if the clans can win the battle, Fergus pays a visit to the witch, who craft an enchanted helmet that can make the wearer's army have false courage in battle. He tells her that he will repay her after the invaders have been driven off. He later takes Merida to his army's encampment, and presents her with his first bow, that he won his first battle with, saying she should win her first battle with it too. He also tells her that he has hired a soldier to teach Merida how to properly use a sword. Merida doesn't think that any man can outdo her with any weapon, but then the soldier easily knocks her down and is revealed to be the rogue warrioress, Mulan. Impressed, the two become friends and Mulan quickly teaches Merida the ways of a smart swordswoman, whilst preventing her from doing foolish things like fighting the cocky MacIntosh. Later, Fergus decides he does not want Merida in any danger, and so tells Mulan to arrange a lesson during the battle. However, Merida hears the war trumpets and races off to see the thick of the battle, and to her horror, she sees a helmeted soldier coming up behind Fergus. She pierces his cloak before he kills Fergus. Two years later, the Witch demands that Merida give her what her father owed her or the entire kingdom will suffer the spell of Mor'du. With help from Mulan and Red Riding Hood, Merida finds her father's helmet and the witch reveals that she was testing Merida to see if she was willing to do what it took to protect the kingdom. She gives Merida a magic ale that will allow her to summon her father's spirit. She pours the ale on her father's grave and sees his ghost. He tells her how proud he is of her. As he disappears, Merida swears revenge on the man who killed Fergus: King Arthur.
- To achieve the mass of Fergus’ kilt, the drape going across his chest has eight layers of cloth folded over and interacting with each other and other garments. The left, right and back sides of the drape have six layers each.
- The DunBroch tartan pattern (worn by King Fergus and family) is physically impossible to make with traditional tartan weaving methods.
- The names and gender of his two Scottish Deerhounds are unknown.
- Fergus' name means "strong man" in Gaelic.
- King Fergus is voiced by the Scottish actor Billy Connolly, who previously voiced Ben in Pocahontas, making him the second Disney character to be voiced by him, but the third to be portrayed by him, the second being Billy Bones in Muppet Treasure Island.
- Fergus bears some resemblance to Stoick the Vast (Hiccup's father) from the DreamWorks How to Train Your Dragon franchise.