The King's Official Birthday Cards

An annual ceremonial observance marking the reigning British monarch's official birthday. Originating in the 18th century as a fixed public celebration held in better summer weather than many sovereigns' actual birthdays, it is most visibly marked in the United Kingdom by Trooping the Colour — a large military parade and flypast — together with gun salutes and the publication of the Birthday Honours list. The official birthday gives an occasion for public festivities, military pageantry and official honours across the UK and in some Commonwealth realms, though individual realms may observe the monarch's official birthday on different dates.