Exemplification under the Great Seal of England of the Act of Parliament of England, ratifying the treaty of Union between Scotland and England. The Treaty of Union is the name usually now given to the agreement which led to the creation of the new state of Great Britain. It states that England and Scotland were to be "United into One Kingdom by the Name of Great Britain".
The Articles of Union, 7 March 1707
Credit: Crown copyright, NRS, SP13/210 (Link to the Online Catalogue entry)