"The colour red of hair shows wrath and treason, as Aristotle wrote to Alexander, maybe that was the colour of Typhon."
"But Aristotle in his Physiognomy writes: Red-haired men are vicious, because they look like foxes. Polemon and Adamantius say: If the colour of hair is more red than due, like the pomegranate, it can't show good things in men, since most of them are keen to the habits of beasts. Adamantius adds: They're insolent and greedy of money. Aristotle calls this colour pyrroiagan, which shows the nature of a deceptive fox. Doctors say that red hair turns white sooner than black. That is, the redness is almost a weakness of hair, which soon grows old."We're not entirely sure about the word pyrroiagan, but we think it relates to the word pyro, as in fire (quite fittingly).
"Plautus, in his Asinaria, depicts Leonidas as red-haired, almost vicious, full of treasons and greedy. Pyrrhus, Akilles' son, was called Neoptolemus, but he was named Pyrrhus after his fiery red hair, as Sevius says. Martial, in order to show that his Zoilus was vicious and insidious, said he was red-haired. The emperor Alexios Komnenos had long and very red hair, like gold."
"Valentinian was red-haired, with beautiful eyes and austere. According to Cedrano, Phocas had red hair.":)