Towards the end of the century, there occurred a blossoming of theoretical activity. In England, Ruskin's ideals underpinned the emergence of the Arts and Crafts movement exemplified by the writings of William Morris. This in turn formed the basis for Art Nouveau in the UK, exemplified by the work of Charles Rennie Mackintosh, and influenced the Vienna Secession. On the Continent, the theories of Viollet-le-Duc and Gottfried Semper provided the springboard for enormous vitality of thought dedicated to architectural innovation and the renovation of the notion of style.