and panoramic battle picture of its day", and its aerial viewpoint was to be very widely followed over the next centuries, though rarely to such dramatic effect. Especially in Northern Europe, small groups of soldiers became a popular subject for paintings and especially prints by many artists, including Urs Graf, who is unusual in that he was a professional Swiss mercenary for many years. These works began to present a less heroic view of soldiers, who often represented a considerable threat to civilian populations even in peacetime, though the extravagant costumes of the Landsknecht are often treated as glamorous. For Peter Paret, from the Renaissance "the glorification of the temporal leader and of his political system – which had of course also been present in medieval art – replaces the Christian faith as a determining interpretive force" in military art. Naval painting became conventionalized in 17th century Dutch Golden Age painting, and from then on artists tended to specialize in it or not attempt it; apart from anything else "Marine artists have always dealt with a particularly demanding class of patron", as J. M. W. Turner found when the "Sailor King" William IV of the United Kingdom rejected his version of The Battle of Trafalgar because of inaccuracy. Hendrick Vroom was the earliest real specialist, followed by the father and son team of Willem van de Velde, who emigrated to London in 1673, and effectively founded the English tradition of naval painting, "producing a stunning visual record of the Anglo-Dutch naval wars, which set the conventions of maritime battle painting for the next 150 years". Vroom had also worked for English patrons, designing a large set of tapestries of the defeat of the Spanish Armada which was destroyed when the Houses of Parliament burnt down in 1834. The 17th and 18th centuries saw depictions of battles mostly adopting a bird's eye view, as though from a hill nearby; this made them less interesting to paint, and the major artists now tended to avoid them. A very different view of warfare is seen in Les Grandes Misères de la guerre ("The Misfortunes of War"), a set of twelve etchings produced by Jacques Callot during the Thirty Years War which follows a group of soldiers ravaging the countryside before eventually being rounded up by their own side and executed. Also in the first half of the 17th century, a branch of genre