resurgence of Celtic motifs, now blended with Germanic interlace and Mediterranean elements, in Christian Insular art. This had a brief but spectacular flowering in all the countries that now form the United Kingdom in the 7th and 8th centuries, in works such as the Book of Kells and Book of Lindisfarne. The Insular style was influential across Northern Europe, and especially so in later Anglo-Saxon art, although this received new Continental influences. The English contribution to Romanesque art and Gothic art was considerable, especially in illuminated manuscripts and monumental sculpture for churches, though the other countries were now essentially provincial, and in the 15th century Britain struggled to keep up with developments in painting on the Continent. A few examples of top-quality English painting on walls or panel from before 1500 have survived, including the Westminster Retable, The Wilton Diptych and some survivals from paintings in Westminster Abbey and the Palace of Westminster. The Protestant Reformations of England and Scotland were especially destructive of existing religious art, and the production of new work virtually ceased. The Artists of the Tudor Court were mostly imported from Europe, setting a pattern that would continue until the 18th century. The portraiture of Elizabeth I ignored contemporary European Renaissance models to create iconic images that border on naive art. The portraitists Hans Holbein and Anthony van Dyck were the most distinguished and influential of a large number of artists who spent extended periods in Britain, generally eclipsing local talents like Nicolas Hilliard, the painter of portrait miniatures, Robert Peake the elder, William Larkin, William Dobson, and John Michael Wright, a Scot who mostly worked in London. Landscape painting was as yet little developed in Britain at the time of the Union, but a tradition of marine art had been established by the father and son both called Willem van de Velde, who had been the leading Dutch maritime painters until they moved to London in 1673, in the middle of the Third Anglo-Dutch War. Early 18th century The so-called Acts of Union 1707 came in the middle of the long period of domination in London of Sir Godfrey Kneller, a German portraitist who had eventually succeeded as principal court painter the Dutch Sir Peter Lely, whose style he had adopted for his enormous and formulaic output, of greatly varying quality, which was itself repeated by an army of lesser painters. His counterpart in Edinburgh,