- “Ha-cha-cha, ladies' night! Where ladies get everything they want! And what they want, is to adore me.”
Mortimer first appeared in the Mickey short Mickey's Rival and has been battling Mickey for Minnie's affections ever since.
Mortimer is said to be Minnie's ex-boyfriend and she possibly left him due to his nature. He is very arrogant and rude, the total opposite of his rival. While he claims he loves Minnie very much, he shows to be incredibly selfish as seen in the cartoon "Mickey's Rival" where he leaves Minnie to be attacked by a bull that he provoked. Not only that, he attempts to flirt with any female character on screen which might also indicate the reason the relationship between him and Minnie was abolished. Also, Mortimer can be rather sexist as seen in "Mickey's Rival Returns" where he feels that Minnie is only a prize to be won.
Interestingly, a different side of Mortimer was showcased in the cartoon Mickey's Mix-Up, where Mickey accidentally sent a heartwarming fax to Mortimer (which was actually meant for Minnie) having Mortimer believe Mickey wanted to make amends, which he immediately agreed to. This shows that, perhaps, Mortimer does hold a softer side, and wouldn't mind becoming friends with Mickey if the latter also wanted to let bygones be bygones. However, this softer side was never revealed again, due to either Mickey revealing the truth about the mix up, infuriating Mortimer, or more likely because the entire thing was used as a comical gag.
Aside from his cocky and sexist attitude, Mortimer proves to be, time and time again, rather intelligent and crafty. He's, on many occasions, managed to manipulate Mickey into a scheme that'd end in the downfall of his relationship with Minnie. For instance, in Big House Mickey, Mortimer managed to fool the town's government into arresting Mickey. In Mickey and the Culture Clash, he manipulated Mickey into believing Minnie desires a more sophisticated boyfriend, resulting in the mouse changing his persona to the point where Minnie believes he's out of her league, leaving her in the hands of Mortimer. Mortimer has one catchphrase which is "Ha-Cha-Cha". Which he says in Mickey Mouse Works and House of Mouse. In some of the comics he says it differently; "Hot-Cha-Cha".
Mortimer is essentially a taller version of Mickey, and seems a bit more human-like. Unlike his rival, Mortimer has whiskers, perhaps referencing how he has a ratlike persona. He has feet the size of Goofy's. Unlike most of the other mouse characters, however, you can see two large teeth close together, like a rat. He is usually wearing jeans and a shirt, but sometimes he also wears a hat.
When Walt Disney was in the process of creating Mickey Mouse, he suggested the name of his new character to be Mortimer Mouse. However, his wife, Lillian Disney, felt the name sounded too pompous, and suggested naming him Mickey, instead. Years later, when developing a new short, the name Mortimer was put to use for a new character, an antagonistic rival of Mickey's for Minnie's affections. Mortimer only appeared in the cartoon "Mickey's Rival" and was never seen in animation again until 2000, when his popularity skyrocketed and landed him roles in several Mickey Mouse related material.
Since then, in most of his appearances, Mortimer's voice has been provided by Maurice LaMarche, which is said to be an exaggerated impression of comedian Jon Lovitz.
In his first appearance, Mortimer was driving by and notice Mickey and Minnie as they were having a picnic. Minnie is thrilled to see Mortimer once again. As soon as Mortimer walks up, Mickey already knows he is bad news just as Mortimer does not like Mickey at all so he attempts to humiliate Mickey and when Mickey shows Minnie how upset he is Minnie states that he is just jealous. Mortimer then tries to impress Minnie by annoying a bull that is over a fence. The plan works until the bull finds a way out. Mortimer rushes and drives away in his car and leaves Mickey to rescue Minnie who eventually remembers why she left Mortimer in the first place.
Mortimer makes a brief appearance in the direct-to-video film Mickey's Once Upon a Christmas. Here, Mortimer is the snooty, profound and wealthy owner of Mortimer's Department Store, and he speaks with a profound tone. His design is noticeably different here; he does not have his buck teeth and is drawn with a mustache instead of his usual whiskers. Minnie Mouse and Daisy Duck are notable employees of the store, and judging by Minnie's low-budget lifestyle, he does not pay well. In Mortimer's brief scene, Minnie hopes to earn the Christmas bonus for her extra hard work, so that she may pay for a wonderful present for Mickey. However, Mortimer only gives her a fruitcake, leaving Minnie without money to buy the gift.
In this series, Mortimer returned to animation as a recurring antagonist to Mickey, now drawn to match his redesign in the comic strip (see below). Mortimer's first appearance in the series was the cartoon Mickey's Rival Returns. In this cartoon, Mortimer and Mickey compete with each other in volleyball. The winner gets to ask Minnie on a date. Originally, Mickey refused the idea being that it would be using Minnie as "some kind of trophy", but Mortimer's arrogance and mocking angers Mickey into competing. Mickey wins, but Mortimer reveals the competition prize to Minnie, causing her to believe Mickey thought of her as a prize (when it was really him). Minnie instead leaves with Mortimer but at the date, he begins to harass her for a kiss. Fortunately, she is saved by Mickey who she forgives (despite the fact it wasn't Mickey's fault in the first place) and has a beach dinner with.
In later episodes, Mortimer is Mickey's neighbor and is still competing with Mickey to win Minnie's heart, or simply trying to ruin Mickey's day. He is apparently wealthy, as he is shown to own far more advanced technology than his rival. One of Mortimer's most villainous roles was in the cartoon Big House Mickey where he falsely accused Mickey of robbing his house, got Mickey sent to prison, and even lied under oath. Mortimer made a guest appearance in the Pluto segment, Pluto Gets the Paper: Mortimer, here he steals the newspaper Pluto was about to get for Mickey, and after a long chase, the dog finally gets back at him by making him bring the paper to Mickey like a dog.
In the television series House of Mouse, Mortimer gets a role as a recurring character. Mortimer appears many times as a guest and tries to trick Mickey and Minnie into breaking up or just flirt with the women. In the series' pilot episode, Mortimer appears briefly, but is seen flirting with Donald Duck's girlfriend Daisy Duck instead. He would go on try to have both Minnie and Daisy all to himself in later episodes. Mortimer proves to be hated by mostly all of the guests at the club, including villains such as Ursula and Gaston. It is even indicated in the episode "Pete's Christmas Caper" that the cruel Pete might even have a dislike for him.
Whenever he's not flirting with Minnie or Daisy or Clarabelle, Mortimer's seen flirting with dozens of females in the audience, such as Anastasia and Drizella from Cinderella, Laverne from The Hunchback of Notre Dame, or even The Queen of Hearts from Alice in Wonderland.
Mortimer's most prominent appearance in the series is "The Mouse Who Came to Dinner", in which he tricks Mickey and friends into believing he is a restaurant critic, and he forces them to treat him like a prince or he will give them a negative review which could close the club. Mortimer is foiled when Lumière is revealed to be the actual critic.
Mortimer has a non-speaking role in "Minnie's Birthday" seen sitting beneath a tree, playing a guitar. In this appearance, Mortimer wears the orange shirt from Mouse Works with yellow polka dots, blue pants and yellow shoes. He was also seen sleeping and sunbathing on the ground.
Mortimer makes his only proper appearance on the series in the special "Super Adventure!" as the main antagonist. Here, he has a supervillain ego named Megamort, who plots to take control over the Clubhouse World by shrinking all the landmarks and storing them within his zeppelin lair. During some time of the plotting, Mortimer forced the humble Pete to act as his minion, ordering him to go around to proceed with his bidding. When the problem reaches Mickey and friends' attention, Ludwig Von Drake creates a machine that transforms the clubhouse gang into a team of superheroes.
Together, they head out and are able to defeat Pete. However, Pete reveals he was forced to fulfill such evil deeds, under the control of "the big boss", who threatened to shrink Pete should he refuse to follow orders. Just then, Megamort arrives and does just that, due to Pete's failure. And with Pete no longer serving him, Megamort goes ahead and wrecks havoc amongst the world himself, leading to everything, including Mickey himself being shrinked and imprisoned. Under their hero egos, Donald, Goofy, Minnie, Daisy, and Pluto travel to Megamort's zeppelin where a battle ensues.
Successfully, they retrieve the shrunken landmarks, but causes Megamort's blimp to go haywire in the process, putting Megamort in great peril. Mickey concocts a plan to successfully save the villainous Mouse, and Megamort, being eternally grateful, apologizes and redeems himself, revealing that his true name is Mortimer Mouse, and that he's the Clubhouse' newest neighbor. With his villainy in the past, Mortimer restores the peace in the Clubhouse world and is welcomed by Mickey and the gang into their circle of friends.
Strangely, Mortimer's appearance in "Minnie's Birthday" seems to have been forgotten here, as he was showcased in "Super Adventure" as the Clubhouse's new neighbor, as if Mickey and the gang had never known him prior to those events. It could be that "Superhero Adventure" chronologically takes place first, despite having been made years later.
Mortimer returns in Paul Rudish's Mickey Mouse animated series, once again as Mickey's rival for Minnie's affections. Here, he retains his original design from Mickey's Rival, but has a white face and black button eyes like the other mouse characters. He appears in the episode "No", where Mickey's inability to say the word "no" is taken advantage of by Mortimer, who asks Mickey to borrow Minnie romantically. Though Mickey isn't able to refuse, Minnie stomps on Mortimer's foot and storms off. Later, a wounded and handicapped Mortimer angrily tells Mickey to keep his girl, believing she isn't worth the stress. In the final scene, Mortimer joins the others in asking Mickey permission to watch TV with him and Mickey responds "yes".
Mortimer made a cameo appearance in the Minnie's Bow-Toons episode "Slumber Party", when Minnie, Daisy, Clarabelle, Millie, and Melody are watching a scary film on TV.
Mortimer actually seems to originate in comics, as he (in different languages at least) made his first appearance in that medium six years before his animated debut. In this first incarnation, he was called Mr. Slicker and appeared in Floyd Gottfredson's first full Mickey Mouse newspaper comic serial, Mr. Slicker and the Egg Robbers. When Minnie Mouse's father, Marcus is in danger of losing his ranch eggs, Mr. Slicker offers aid financial return for Minnie's hand in marriage, and Mickey suspects him. In the end, Mickey proves it was Slicker who was behind the thefts.
Around the time the cartoon short Mickey's Rival came out, Gottfredson adapted it into a storyline in the Mickey Mouse Sunday strip, but with a noticeably different plot. Mickey goes over to Minnie's house to visit, only to be greeted by Mortimer, who is also visiting Minnie. After Minnie introduces him to Mickey, Mortimer proceeds to make Mickey look like a fool in front of her. Each day, he keep pulling pranks on Mickey in hopes of getting rid of him. In the end, Mickey got the better of him, and Minnie kicked Mortimer out.
Five years later, Mortimer returned to the daily comic strip as Montmorency Rodent (surname pronounced "Ro-dawn"), or Monty for short, in Gottfredson's storyline "Love Trouble". Monty claims to be of the Social Elite and, just like in his previous appearance, does everything he can to make Mickey look like a fool in front of Minnie, especially at Patricia Pigg's party. Eventually, with help from his cousin Madeline, Mickey manages to expose that Monty is really nothing more than a thieving chauffeur in front of the real Social Elite. Although Gottfredson did not use Monty again after this, this version of Mortimer's design would go on to be the default design of the character in later comics, as well as his above-mentioned return to animation.
The character returned again in "The Copper's Catch", published in Walt Disney's Comics and Stories #67, now called Mortimer Rodent, and officially becoming a recurring antagonist to Mickey afterward. In later comic appearances under other writers, Mortimer sometimes teamed up with Mickey's other rivals, such as Pete, Sylvester Shyster, and Muscles McGurk. In some comics, it was shown that Mortimer is rich and lives in a mansion, and he can also fly a plane.
Mortimer is also featured as a unlockable and playable character in the app game Disney Crossy Road.
Mortimer has not yet made any live appearances in the Disney theme parks. However, a mural with several classic Disney characters during the Disney California Adventure expansion was seen with Mortimer being one of the characters featured. Also at the park, Mortimer's namesake is featured in the shop Mortimer's Market which is located on Buena Vista Street.
- Mortimer's name, besides being the original name for Mickey, derives from the name of Disney's former pet mouse of the same name.
- Although Mortimer wasn't used that much in the original cartoons, he has been used a lot in the comics particularly the comics from overseas, the most popular ones being Brazil, Italy and France.
- Mortimer bears resemblance to an obscure character, Ruffhouse Rat, who is a cousin of Minnie's from an early Mickey Mouse newspaper comic.
- In the Berke Breathed strip Bloom County, there is a Mortimer Mouse, who is a stubbly, surly mouse who wears the same outfit as Mickey's, but more disheveled. He is annoyed that he was drafted during the Second World War, during one battle he suffered an injury where a Panzer tank ran over his foot, while at the same time Mickey went on to fame and fortune. This parody was ended after Breathed was threatened with a lawsuit from Disney for unauthorized parody in 1988. Interestingly, Disney had better relations with Berke Breathed twenty years later when they based a film on his children's book Mars Needs Moms.
- According to voice actor, Maurice LaMarche, his voice of Mortimer is an exaggerated impression of comedian/actor, Jon Lovitz. He would later use this voice for Zix from Jimmy Neutron.