Ranking high, historically, they rebuilt Athens (6)

I believe the answer is:

thanes

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'ranking high historically they' is the definition.
The definition suggests an adverb but the answer is not.

'rebuilt athens' is the wordplay.
'rebuilt' indicates anagramming the letters.
'athens' is an anagram of 'THANES'.

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I've seen this clue in the Evening Standard.

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