N.H. Rev. Stat. Ann. § 104:1

No sheriff of any county shall exercise such office, or perform any act therein, or receive any fee or salary therefor, until he shall have deposited in the office of the secretary of state a copy of the record of his birth, attested by the clerk of the town in which he was born, or, if there is no such record, an affidavit, sworn to and subscribed by himself, stating, according to the best of his belief, the date and place of his birth.