The last self portrait by one of the very greatest of all portrait painters will be offered for sale this winter after almost 300 years in one family's collection.

Few artists have exerted more influence, for good or ill, over British art than Sir Anthony van Dyck, the dashing Flemish painter who became the official portraitist for Charles I’s court.

Modern detractors argue that van Dyck is to blame for 400 years of flattery and airbrushing in depictions of the famous and the powerful.