THE LONDON GAZETTE, England, Feb. 9, 1811  During the latter years of his reign, King George III was declared mentally incapable of carrying on his duties. Thus, the "Care of the King During his Illness Act" of 1811 came into play, giving his son, the Prince Regent, and the future King George IV, the authority to act in his father's behalf.
This issue, on page 3, with a dateline of "Westminster, February 5, 1811", has that report that the Royal Assent had been given to: "An Act to provide for the Administration of the Royal Authority, and for the Care of His Majesty's Royal Person, during the Continuance of His Majesty's Illness, and for the Resumption of the Exercise of the Royal Authority by His Majesty."
Thus, February 5 is considered the beginning of the Regency. In 1820 George III would die and the Prince Regent would be coronated as King George IV.
Complete in 26 pages, 7 1/2 by 11 3/4 inches, very nice condition.