Contrary to popular belief, the Celts did not originate in Great Britain, but in central Europe. By the second century BC, the Celts had expanded to most of Europe before being pushed back to the British Isles by the Romans (Seriously, what did the Romans ever do for us?)
In ancient times, the Celts were known for their sexual freedom, including homosexuality and female promiscuity. Diodorus said that the women were beautiful, but the men preferred to lay with each other.
Celts also shared a different view than their contemporaries regarding women. It was not unusual for women to assume kingship, or become warriors. Female warriors were common especially among the insular Celts (British Isles). Women were also able to divorce their husbands.
According to Wikipedia:
Under Brehon Law, which was written down in early Medieval Ireland after conversion to Christianity, a woman had the right to divorce her husband and gain his property if he was unable to perform his marital duties due to impotence, obesity, homosexual inclination or preference for other women.
The Celts believed the soul resided in the head, so unlike the Aztecs with the heart, the head was prized above all else.
Apparently, they had a reputation as head hunters. They were also vicious warriors, often described by their enemies as wild and savage (Mostly the Romans).
It is also asserted by some scholars that the Celtic warriors fought naked, which was terrifying since they were all spectacularly fit.
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