The archives of the principal secretaries of state of Elizabeth I, as they survived in official custody. The papers are evidence of the great variety of business passing through the secretaries' office, and the presentation of the most important matters for consideration by Elizabeth I and the Privy Council. The series also includes items from outside the reign of Elizabeth I, where either the major part of the item referred to that reign, or the document in question was a later transcript of an Elizabethan document.

The series also contains many larger items of considerable significance including certificates of musters 1569-1573, Admiralty warrants, returns of aliens in London and Southwark in 1571, valuations of benefices throughout England and Wales in 1574, lists of justices of peace in liberi pacis, etc. Also includes some papers relating to the English/ Scottish border (originally in SP 59)

These State Paper Office documents were brought together in the nineteenth century for the purpose of publication in calendar form.