Arnold Phillip Shortman is a fictional character created by Craig Bartlett. He has featured in claymation shorts and comics, but his main role has been the main protagonist of the Nickelodeon animated television series Hey Arnold!.
His head is shaped like a giant football, thus earning him the nickname "Football Head".
Arnold was created in 1985 by Craig Bartlett, who was also responsible for the clay-animated Penny shorts on CBS's Pee-wee's Playhouse. The original Arnold was visualized as a rich, prep school kid with a vivid imagination, who always wore a prep-school uniform and his signature cap, and was rendered in clay in a series of shorts, one of them televised in 1991 on Sesame Street, and continued to air there, even after the Nick version debuted.
In 1991, the Hey Arnold comic stories, written and drawn by Bartlett (who's also a comic book artist), were published in Simpsons Illustrated magazine (Bartlett is the brother-in-law of Matt Groening, creator of The Simpsons).
The familiar, cel-animated Arnold came about in the mid-1990's when Nick picked up the new series. In the TV series, Arnold is a 4th grader who lives in a boarding house with his paternal grandparents, Phil and Gertrude. Apart from the animation style, Nick's Arnold now wears a sweater, with his plaid shirt untucked (often mistaken for a kilt). Only Arnold's beloved cap remained from the original wardrobe. He no longer wore a school uniform in the TV series because he attends a public school. Now he wears a dark blue jacket to go with his outfit.
Arnold is a calm, nice, kind, optimistic, upbeat and smart idealist who always sees the best in people despite how unkind, outlandish or sneaky some of them may be. "Football Head" as his peers and grandparents call him, often goes out of his way to help others even if it's not in his best interest to do so. Arnold is also a bit of a daydreamer in the earlier episodes. Although he can be a bit irritable when he's pushed too far.
Arnold resides in a boarding house called the Sunset Arms and goes to an elementary school simply named P.S. 118. Arnold's excellent upbringing is due to the way his paternal grandparents and boarding house residents raised him. He's a respectable young gentleman at home and at school with his peers and teachers.
Arnold has often been shown to be ignorant and blind when it comes to romance and love. For example, he never figured out Helga was "Cecile" in "Arnold's Valentine" (even though it was obviously her), and he doesn't seem to process Helga's incomplete love declarations in "Grudge Match" and the chapter book "Arnold's E-Files". Furthermore, he continually refused to accept that Lila Sawyer didn't return his feelings despite being told so repeatedly. Sometimes, Arnold is shown to be a bit shallow, as he only liked Lila and Ruth because they were pretty and never really took time to know them.
Arnold has a natural gift for giving advice and guidance to others. He often helps the other kids and even adults with their problems. In "Oskar Can't Read" Arnold helps Oskar Kokoshka learn how to read for the first time and in "Oskar Gets a Job" Arnold helps him find a Job. He has even helped his Grandpa Phil on several occasions in the episode "Steely Phil", Arnold helps Phil overcome his fear of facing Robbie Fisher in the city Chinese Checkers tournament and in ""Grandpa's Sister"" Arnold helps him reconnect with his sister Mitzi after 70 years. During the episode "Chocolate Boy" Arnold helps Chocolate Boy kick his addiction to chocolate a change that could potentially have saved his life.
In early episodes, Arnold is shown to be somewhat gullible such as the episode, Cool Jerk, where he starts hanging out with a gangster.
Arnold's bedroom is full of interesting technology: a remote control that commands everything in his room, a powerful computer and a collapsible couch. His entire ceiling comprises of an expansive skylight that includes a trapdoor where people on the roof can come in. Most of his room is blue since it his favorite color.
Arnold is a natural athlete with impeccable baseball and football skills; he's often playing sports with his friends at Gerald Field.
Though his religion is never explicitly mentioned on the show, it is implied that he belongs to the Roman Catholic faith in a comic titled "Arnold Eats His Dinner". He is involved in a prayer which includes a mention of the Holy Ghost (God). He is also seen attending church in "Arnold Escapes From Church."
Arnold was named after his mother's father. The name Arnold is of German origin, and stands for "the eagle rules" or "strong as an eagle."
Arnold's last name has never been revealed on the show. With the exception of a few secondary characters (including Sid and Brainy), the only other notable characters whose surnames are unknown are Arnold's grandparents. They presumably have the same last name as Arnold, since in "Parents Day" and "The Journal" it is revealed they are his father's parents. The mystery surrounding Arnold's full name became a running gag on the show, by the last name almost being revealed, then someone or something interrupting or otherwise preventing it from being heard (much like the state Springfield is in on The Simpsons). Some notable occasions when the name is almost revealed include:
- In a commercial for the show that aired in the early part of the show's run, Arnold talks to the viewer to straighten out some facts about himself (such as the revelation that his notable red outerwear is a shirt, not a skirt). He ends with, "And yes, I do have a last name. It's..." at which point the screen turns into static and the sound cuts off.
- In the episode "Fighting Families", Arnold wins the school's raffle drawing for the chance to be on the game show Fighting Families. The lady doing the drawing announces, "The winner is Arnold...hmm, there seems to be a smudge over the last name." Here it is revealed that Arnold is the only one in the school with this first name, thus making his surname somewhat unnecessary.
- A similar instance to the one above occurs in "Eugene, Eugene!", where Tim Curry's character is casting the school kids for an upcoming play, and says, "I can't read my own handwriting", when he's casting Arnold as the villain. However, that scene did at least reveal Lila's last name (Sawyer, as mentioned above).
- In one episode, "Crush on Teacher", in which Helga does one of her many passionate monologues about her love for Arnold, she says that she would one day like to become "Mrs. Arnold...wait, what is his last name?", revealing that she is just as clueless as the viewers.
- In the episode "The Journal", Phil is reading the part of Miles's journal that recounts his and Stella's wedding. He gets to the part when they are pronounced "Mr. and Mrs...." at which point Grandma interrupts with a loud belch.
- In the episode "Married", Helga dreams that she is married to Arnold, and that she is the president. In her opening speech, she introduces Arnold as "Arnold Pataki."
- Series creator Craig Bartlett had been planning to finally reveal his last name in a second feature film for the series, which would also deal with his search to find his parents. Craig mentioned in a subsequent online chat: "I had an idea for the Jungle Movie (how Bartlett refers to the planned film), in the opening scene, a man comes to the door of the boarding house, and Arnold signs his name. Right, that's how you find out." Initially, problems between Bartlett and Nickelodeon, as well as the low gross of the first film, led to the cancelation of this second film. However, Nickelodeon has confirmed that Craig Bartlett will return to make the Jungle Movie
- In a 2006 chat with Hey Arnold! fans, Bartlett revealed that Arnold's grandpa used his last name throughout the series, almost confirming that Arnold's last name is "Shortman".
- In some episodes other characters can be seen referring to Arnold as Shortman (In the beginning of Arnold Visits Arnie, Helga is telling the other characters their positions in a game of baseball she is quoted saying "Looks like you're on Shortstop, Shortman"
- In a commercial for Hey Arnold, where Bartlett is interviewed, Bartlett promises that Arnold's last name will be revealed, and that the audience has been hearing his name throughout the entire series. Grandpa frequently calls Arnold "Shortman."
- "Shortman", if it is assumed to be Arnold's surname, is an actual surname. Its origin is English, with the earliest known variant of the surname recorded in Dorset in 1176. 
- In 2016 in an interview with Buzzfeed it was ultimately confirmed that Arnold's last and middle name are indeed Phillip (his middle name) and Shortman and that he would reveal it in the film (despite the reveal already being spoiled in the interview). 
According to the episode "The Journal", Arnold was born while his parents were on an earlier expedition in the jungle to bring medicine to the natives. His birth coincided with the eruption of a nearby volcano, which the locals believed to be an indication that Arnold would one day become a messiah of sorts who would save the world from a great danger. Arnold was not told of these events until later in the series when it was revealed by his grandfather. It is unknown how the "prophecy" may have fit into the series had it continued.
In a chat, Craig Bartlett mentioned that he was supposed to be semi-worshiped by the Green-Eyed people, and that a football-headed figure is an important symbol for their culture.
He was born on the 7th day of an unknown month ("Married"). Some fans agree that he was born on October 7th, the day the first episode of the series aired for the first time. But that would create a flaw on the history, since Arnold's parents left him on October 5th, and they celebrated his 1st birthday some time before leaving the Boarding House once and for all. Though others believe that Arnold's parents may have disappeared before his second birthday.
Additionally, in a logged chat Craig Bartlett said, "...Arnold is like me in that he has to think things over a long time, before coming to a decision. That I believe is a Libra characteristic. Go Libras." (See the chat transcript) This implies Arnold being a Libra, which would make his birthday fall sometime between September 24th to October 23rd. It is most likely on October 7, as in ("Married"), he mentions his birthday is on the 7th of a month.
Arnold never dates anyone, but he does have crushes on girls. Throughout the series, his relationships are one-sided on his side.
CrushesArnold has had two major crushes in the series: 6th-grader Ruth P. McDougal (during Season 1), and a classmate named Lila Sawyer (who was introduced in Season 2). His crush with Ruth ended in "Arnold's Valentine" after he went on a date with her and realized she wasn't his type. His crush on Lila ended when he became embarrassed after she overheard him tell his best friend's younger sister, Timberly, to help convince Lila to reciprocate his feelings in "Timberly Loves Arnold". In the episode "Crush on Teacher" Arnold develops a crush on his substitute teacher Miss Felter, and even went as far as to think she had a crush on him too. The crush on her ended at the end of the episode when Arnold found out that Miss Felter didn't actually have a crush on him.
See Helga and Arnold.
Arnold's best friend is Gerald Johanssen, whose relationship dates as far back as pre-school. The pair have a distinct handshake consisting of putting two thumbs-up fists together and wiggling the thumbs back and forth.
Over the course of the series, Arnold has had a handful of voice actors. In the pilot, Arnold's voice was provided by J.D. Daniels, though when the series came to fruition, Daniels was not brought on. During Season 1 and "What's Opera, Arnold?" Toran Caudell provided the voice of Arnold, though he left the show after the first season due to his voice changing, returning soon after as Wolfgang. Phillip Van Dyke was brought on as the voice of Arnold for the second and third seasons. However, like Caudell, Van Dyke's voice also underwent changes, causing another change in voice actors (though Van Dyke would return during Season 5 to voice Ludwig in "New Bully on the Block"). In Season 4, Spencer Klein started voicing Arnold, and continued to provide his voice all the way through Season 5 and the movie. The last two episodes "April Fool's Day" and "The Journal" feature Alex D. Linz as the voice of Arnold instead. His final voice actor as of 2017 is Mason Vale Cotton.