Anakin is dirty blond in AOTC, ROTS, CW 03-05. TCW, for some reason, decided to give him a darker brown. Despite that, Luke is blond and becomes a dirty blond by ESB and ROTJ because Anakin is. Also both Mark Hamill and Hayden Christensen have Swedish ancestry.
Young Anakin in TPM looks what I'd call blond, and in AOTC and ROTS, I'd consider his hair on the darker end of dirty blond, a change in hair color that I think isn't that uncommon. My experience is that people's hair can definitely get darker and change in other ways as they come out of childhood. Anyway, based on Anakin's hair color in the PT it didn't seem that crazy to me that Luke would be blond in the OT. Apart from that, genetics are kind of complicated. There's phenotype (the traits that we actually see manifested in the person-think "phenotype" and "physical" as a memory trick) and then there's genotype (the actual genetic makeup of a person in terms of their alleles). The phenotype of a person with a recessive and dominant allele for a trait could be identical to someone with two dominant alleles for that same trait, but the genotype would be different. In the case of the former, the recessive allele could be passed on to future offspring and could even appear in the phenotype of that future offspring if it is paired with a recessive allele from the mate/partner. And that is in the case of simple dominant-recessive traits controlled by a single gene. My understanding is that human hair color (like human eye color) is more complex than that since it is controlled by multiple genes, explaining why there is such wide spectrum of human hair color. My thought is that not only could Anakin at least be considered blond at some points in his life and dirty blond at others, but there must have been some recessive blond alleles in Shmi that she passed to her son. Padme also likely inherited some recessive blond alleles from her family that she passed onto Luke.
I myself am an example of that. As a child my hair was extremely blond, almost like Billy Idol's or Batty's hair in Blade Runner. As I grew older it became increasingly darker. Recently my mom even called it "black". I don't quite agree. I'd call it "brownish" or something, but not totally black. And one of my nieces had really curly hair when she was a small child. Now she's a teenager and her hair is completely straight.
People's hair color can change, based on their environment, diet and even just with age and their own development. I had red hair till I was around Kindergarten, and it got darker and darker brown up until like 3rd grade. My mom had the same thing. In Anakin's case, I imagine his hair simply was a lighter blonde just cos of being sun bleached while on Tattooine-same with Luke I guess, although Luke retained much blondeness.
Luke has light brown hair, maybe sun bleached on tatooine, but darker by TESB and RotJ. Mark even joked that his son asked why he had yellow hair on the action figure and he told him that they used all the brown paint on Uncle Harrison's figures.
And frankly Lucas wanted a protagonist who looked like Flash Gordon, as shown in Ralph McQuarrie's illustrations. I'd say Mark Hamill being blond is probably one reason why he won out over Lucas' runner-up choice for the role, Will Seltzer, who was slightly older and had curly dark-brown hair. (Hamill came late to the auditions and Seltzer was Lucas' first choice at that point - intended to be cast alongside Christopher Walken as Han Solo!) Lucas later gave Seltzer a role in More American Graffiti by way of apology, but that didn't do much for his career. The only other major film role Seltzer has that I know of is as the villain Mr. Putnam in glorified Nintendo advertisement "The Wizard".
Hair darkens as you age. Blond hair is common in youth. The sun bleaching Hamill's hair also a factor. But for whatever reason Young Indiana Jones actors had the brown hair with the blond highlights. River Phoenix they made more a bottled blond in the movie - which he was kinda known for during his heyday. Probably was a California surfer/ beach boy thing Lucas had a fascination for his young leads.
The Flash Gordon connection does seem relevant here. In the 1974 Star Wars rough draft , the young Jedi protagonist Annikin Starkiller implicitly has dark or brown hair, since his initial romantic rival for Leia's hand, Clieg Whitsun, is explicitly described as blond. Annikin's younger brother Deak, who dies early on, is also blond, so probably Lucas envisioned somebody with dark hair & light eyes, like Elvis Presley, or Jeffrey Hunter in The Searchers. It probably didn't escape his notice either that Hunter played the captain of the Enterprise, Christopher Pike, in the first Star Trek TOS pilot. The "dark-haired Anakin" idea may also be one reason Lucas chose to cast Sebastian Shaw as Anakin in ROTJ. In The Searchers Hunter played a character who was supposed to be one-quarter Native American - and in the Journal of the Whills 1973 outlines, the young "Padawan-Jedi" protagonist is named Chuiee II Thorpe, after the part-Native American celebrated athlete Jim Thorpe. So that version of the young Jedi hero character was probably supposed to be multiracial as well. Or at least, perceivable as such. I could see a young Johnny Depp being cast in that role, for example.
I know it sounds stupid but I've always imagined Padme to be the one with blonde hair and light eyes and Anakin to be dark-haired with brown eyes. Have you ever noticed that a lot of the female characters in Star Wars are brunette while a lot of the males are blond? I think Star Wars is special in this regard. In real life I honestly don't know many couples where the woman has darker features than the man, for example.
Well Nick Nolte was close to being Solo and so was a dark haired Kurt Russel. I think Lucas was looking looking for at least one blond male lead, probably didnt necessarily have to be Luke. Some of McQuarrie's early art features both a blond Han Solo and a blond concept female Skywalker/Starkiller character before it was split into Luke and Leia.
On my dad’s side his lineage is German... so all us kids had really blonde hair growing up, especially being out in the sun all the time... I can only imagine what TWO suns would do... Now mine, naturally, is a mousy brown... but the roots get golden if I have sun exposure.
I'd like to know where the idea of Anakin being blond like Luke (Hayden + Jake Lloyd) came from. Sebastian Shaw's Anakin was definitely dark-haired (with blue eyes though) and I kinda like this contrast compared to his son. Hayden looks too similar to Mark Hamill and that's boring as hell. Although Anakin and Luke are father and son, they are still two different Jedi knights who chose different paths. So why shouldn't Leia for example take more after her father and Luke after his mother? Why didn't they make Padme blonde? Maybe it is silly and highly superficial to cast someone based on his appearance, I know - but still...
Call me literal but based on the sudden change at the end of TPM I thought Anakin actually always was blonde and he just continued dying his hair brown in the sequels, which wouldn't make much sense except he kept hoping to impress Obi-Wan.
Luke spent the most time out of all of them living under twin suns. His hair is sunbleached. You're welcome.
Lucas was going for the parents being reflected in their children. Both physically and mentally, with differences as well.
Add me to the list of people with blonde, almost white blonde, hair as a kid who grew up to have brown hair. I also spent a stupid amount of time playing in the sun and had a very sexy tan to go along with the blonde hair.
Ever hear of genetics? There is such a thing as recessive or non-dominant genes that become obvious only after generetions sometimes. My nephew has afro hair even though both his parents have 100% straight hair. "Bleaching" by sun has nothing to do with this.