Royal Standard of Frederick Augustus, Duke of York and Albany (1763-1827). Silk with a linen hoist, with the design painted on. The provenance is via Captain John Manley (1745-1816) who commanded the frigate 'Syren' escorting the 1793 expedition to Flanders. The captain's log of the ship for the 26 February 1793 states 'His Royal Highness the Duke of York came on board, saluted him with 21 guns & hoisted the standard.' ADM5/874. A similar Royal Standard but without the wheel symbol of the Bishop of Osnabrück is held by Cheltenham Museum and Art Gallery, having been passed down through the family of Captain John Cook. The painting of the flag is in a very similar hand to the NMM example and the Cheltenham flag is marked on the hoist 'Deptford Yard 25 Janry 1799'.

In the first quarter, the arms of England and Scotland impaled; second quarter: azure, three fleur-de-lis, or (France); third quarter: azure, a harp, or (Ireland); fourth quarter: the arms of Hanover. The latter are gules, two lions passant guardant in pale or (for Brunswick); or, semé of hearts gules, a lion rampant azure (for Luneburg); gules, a horse courant argent (for Westphalia). Over all, argent, a wheel, gules (the symbol of the Bishopric of Osnabrück, a principality of which Frederick was the elected ruler from 1764 to 1803). The standard has the Duke of York's label with three points, the centre point with St George's cross.

The second son of George III, Prince Frederick, Duke of York and Albany was appointed by the king to command the British forces in Flanders in 1793. The campaign, in cooperation with allied Austrian forces, enjoyed some initial success but ended with a winter retreat in 1794-5 and the British being driven out of Belgium. York was made commander-in-chief of the army in 1798 and commanded a second invasion of the Netherlands in 1799 with a corps of the Russian army. This was also a failure. Although not an effective field commander, during his two periods as commander in chief, the Duke encouraged promotion on merit and improved the training of officers.