Wooden stakes or pointed sticks forming a fence, or the regions within a territory's borders.
From Old French pale, from Latin palus (stake or palisade). The 'territory' meaning developed in Middle English when 'the Pale' referred to English-controlled regions in Ireland.
The word 'beyond the pale' originally meant literally beyond the wooden fence boundaries of English Ireland—so calling someone's behavior 'beyond the pale' is still a 700-year-old reference to leaving the safety of a fortified zone.
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