They bleached it through washing it in lime. Then they comb it back from their foreheads.
They bleached it by washing it in lime and combing it back!  Crazy to think of that happening so long ago.
I just dyed my hair light purple. I am really excited about it! Neat, hair coloring can be done at home or by a hairdresser, which way did you go? I went to a hairdresser to have it done. Cool, the Celtic people was described by Diodorus Siculus, a Greek Historian, to have dyed their hair blonde. That's really cool! How did they manage that?
Their hair is blond, but not naturally so: they bleach it, to this day, artificially, washing it in lime and combing it back from their foreheads.