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In page Eustace IV, Count of Boulogne:

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This clearly had not been Stephen's first attempt at crowning Eustace as John of Salisbury reports that Celestine II had written to Archbishop Theobald as early as 1143 forbidding him 'to allow any change to be made in the English kingdom in the matter of the crown', a policy that was maintained by Celestine's immediate successors.[4] Eustace's mother, Matilda of Boulogne, died on 3 May 1152, making him the count of Boulogne.[citation needed]