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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We hereby consent to the use in this Amendment No. 2 to Registration Statement No. 333-136287 on Form S-1 of our reports dated August 3, 2006 relating to the consolidated financial statements and financial statement schedules of OneBeacon Insurance Group, Ltd., which appear in such Registration Statement. We also consent to the references to us under the headings "Experts" and "Selected Financial Data" in such Registration Statement.

PricewaterhouseCoopers LLP
Boston, Massachusetts
October 6, 2006

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CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM