I recall some years ago I was hanging out with a couple of Israeli girls. One was Ashkanasi the other an Arab Jew originally from Yemen. We got to speaking about King David and the Ashkanasi went to great length to tell me that KIng David was light skinned with Red Hair. ....
Yeah, this is a notion that's been kicking around for about 2000 years or so, and it is almost certainly incorrect. It's not entirely impossible that David could have been a redhead: light hair of any shade was extremely, extremely rare in the ancient Middle East. I find it deeply unlikely that David would have been a redhead: but of course, nothing is entirely impossible.
But the notion that he was stems from what is very likely a mistranslation. In 1 Samuel, when David is described in his youth, one of the adjectives used in the Hebrew is the ancient poetic term
admoni. The root of this word is
adom, meaning red, and it is rare but possible to use a variation like
admoni in reference to red hair-- Esav the brother of Jacob was nicknamed
Edom for that very reason. But the likeliest translation, the one that grammatically makes the most sense, is "ruddy," meaning that David (an outdoorsy and athletic person by all acounts) was tanned and a bit windblown, and had that slight flush to the skin that indicates the glow of good health.
I cannot recall at the moment how the Septuagint translates the word-- they may be responsible for the mistranslation. But if not there, then it was the Vulgate, which translates the word as
rufus, which, while it could be used to denote ruddiness, was commonly used in Latin to mean "redheaded." It wouldn't shock me to learn that the mistranslation came from the Vulgate: Jerome could be a careless translator, though he had his moments.