Command flag as used by the Generals at Sea during the Commonwealth period. The flag is made of red wool bunting with a linen hoist. It is hand-sewn with an appliqué design showing a wreath of laurel and bay branches surrounding two shields charged with the cross of St George and the harp of Ireland. The flag has been incorrectly made up with the shields upside down. The flag was preserved for many years at Chatham dockyard where it was shown to George III in 1781 (see 'Gentleman's Magazine', March 1803, p. 220.)

The government abolished the Royal Standard in 1649, and the Union Flag as the symbol of the unification of the crowns of England and Scotland also went out of use. During the 11 years between the execution of Charles I and the restoration of the monarchy a variety of flags based on the cross of St George impaling the Irish harp were worn at sea. On the new jack, the cross and harp occupied the whole flag.