The Royal Commission on Historical Manuscripts was appointed under Royal Warrant in 1869 to make enquiry as to the places where manuscripts and private papers of historical interest were located and to report on their contents. The terms of reference were extended in 1959 to include the commission's current functions.

With the creation of The National Archives in April 2003, the warrant was amended to allow the Keeper of Public Records to become the sole Historical Manuscripts Commissioner.
 

ELIZABETH THE SECOND, by the Grace of God of the United Kingdom of Great Britain and Northern Ireland and of Our other Realms and Territories QUEEN, Head of the Commonwealth, Defender of the Faith, To all to whom these Presents shall come,

Greeting!

WHEREAS it was represented to Her late Majesty Queen Victoria that there were belonging to many Institutions and Private Families various Collections of Manuscripts and Papers of general Public Interest a knowledge of which would be of great utility in the illustration of History, Constitutional Law, Science and general Literature; that in some cases these Papers were liable to be lost or obliterated, and that many of the possessors of such Manuscripts would be willing to give access to them and permit their contents to be made public provided that nothing of a private character or relating to the Title of existing owners, should be divulged:

AND WHEREAS it appeared to Her Majesty that there would be considerable public advantage in it being generally known where such Manuscripts and Papers were deposited, and that the contents of those which tended to the elucidation of History, and the illustration of Constitutional Law, Science and Literature, should be published; Her Majesty did accordingly, by Royal Warrant bearing the date the second day of April, one thousand eight hundred and sixty-nine, appoint Commissioners to make inquiry as to the places in which such Manuscripts and Papers were deposited, and for any of the purposes therein mentioned:

AND WHEREAS by Royal Warrants bearing date the eighteenth day of December, one thousand eight hundred and ninety-seven and the twenty-seventh day of March, one thousand nine hundred and nineteen, new Commissions were issued for the purposes specified in the original Commission above referred to:

AND WHEREAS by Warrant under Our Royal Sign Manual bearing date the fifth day of December, one thousand nine hundred and fifty-nine, We deemed it expedient that the terms of reference to Our said Commissioners should be revised and extended:

AND WHEREAS We have deemed it expedient that the responsibilities of the said Commission be exercised by a sole Historical Manuscripts Commissioner.

NOW KNOW YE that We do by these Presents will and ordain that Sarah Jacqueline Tyacke, for so long as she shall hold the Office of Keeper of Public Records, and any persons who shall succeed her in that Office, for so long as they shall hold it, shall act as sole Historical Manuscripts Commissioner, and accordingly We authorise and require Our said Commissioners hitherto appointed and still holding office to cease to exercise the powers and privileges conferred upon them as Chairman and Members of the said Commission.

AND We do further by these presents Will and Ordain that Our said Commissioner shall make enquiry as to the existence and location of manuscripts, including records or archives of all kinds, of value for the study of history, other than records which are for the time being public records by virtue of the Public Records Acts; with the consent of the owners or custodians inspect and report on them; with the consent of the owners or custodians reproduce and publish or assist the publication of such reports; record particulars of such manuscripts and records in a national register thereof; promote and assist the proper preservation and storage of such manuscripts and records; assist those wishing to use such manuscripts or records for study or research; consider and advise upon general questions relating to the location, preservation and use of such manuscripts and records; and promote the co-ordinated action of all professional and other bodies concerned with the, preservation and use of such manuscripts and records.