This book tells the story of a fertile European country that, as a result of over-population and military armament, over-exploited its fields and forests in a non-sustainable fashion. By the eighteenth century Denmark, along with other European countries, found itself in an ecological crisis involving clear felling of forests, sand drift, floods, inadequate soil fertilisation and cattle disease. This crisis was overcome by a green biotechnological revolution that changed the whole pattern of agriculture, and by the abandonment of wood as a raw material and source of energy in favour of coal and iron. This book outlines the background of the present-day ecological crisis, both in the industrial world and in developing countries, and is the first attempt to understand early modern Europe from a consistently ecological viewpoint.