Parliamentarians were on one side of this chair, swivelling around (7,5,3)

I believe the answer is:

english civil war

'parliamentarians were on one side of this' is the definition.

'chair swivelling around' is the wordplay.
'around' indicates an anagram.
'chair'+'swivelling'='chairswivelling'
'chairswivelling' with letters rearranged gives 'ENGLISH CIVIL WAR'.

I've seen this clue in The Guardian.

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