¹ The basis of modern research is still Delbrück, Hans, Geschichte der Kriegskunst im Rahmen der politischen Geschichte (7 vols., Berlin, 1900–36)Google Scholar, for present purposes especially vols. III and IV. See also Lot, F., L'art militaire et les armées au moyen age en Europe et dans le proche orient (2 vols., Paris, 1946)Google Scholar; Oman, Charles, A history of the art of war in the XVIth century (London, 1937)Google Scholar. Among the many more recent studies the following merit particular mention: Verbrüggen, J. F., The art of warfare in Western Europe during the Middle Ages (Amsterdam, 1977)Google Scholar; Michael Roberts, ‘The military revolution, 1560–1660’, and ‘Gustav Adolf and the art of war’, both originally published in 1955–6 and reprinted in Roberts, 's Essays in Swedish history (London, 1967), pp. 195–225, 56–81, respectivelyGoogle Scholar; C., Gaier, ‘La cavalerie lourde en Europe occidentale du Xlle au XVIe siècle’, Revue Internationale d ‘Histoire Militaire, xxxi (1971), 385–96Google Scholar, and finally Howard, Michael, War in European history (Oxford, 1976).Google Scholar

² The expression is Hans Delbrück's, Kriegskunst, iv, 137.

³ Michael Roberts, ‘The military revolution, 1560–1660’ (above, n. 1). The article is a revised version of Professor Roberts's inaugural lecture at the Queen's University of Belfast, 21 January 1955. A necessary corrective to Roberts's article is provided by Parker, N. G., ‘The military revolution, 1560–1660-a myth?’, in Parker's Spain and the Netherlands 1550–1659 (Glasgow, 1979). PP. 85–103.Google Scholar

⁴ Gaier, ‘La cavalerie lourde’. The article is a revised version of a paper read at the XIIIth International Congress of the Historical Sciences in Moscow, August 1970.

⁵ Michael Howard, War, particularly chapters 1–3.

⁶ Roberts, ‘Military revolution’, p. 210.

⁷ Gaier, ‘La cavalerie lourde’, p. 396.

⁸ There is no study of the Danish aristocratic knight service available in any of the major European languages. Recent studies in Danish are Knud Jespersen, J. V., ‘Rostjeneste, Ridderhaer og Militaer Revolution 1525–1625’, Krigshistorisk Tidsskrift (1974), 3–38Google Scholar, and Rostjenestetaksation og Adelsgods (Odense, 1977) - with an English summary. The following account is based mainly on these two studies.Google Scholar

⁹ A royal fief could be granted through 'salaried enfeoffment’ (forlening på regnskab), i.e. the vassal was obliged to present detailed accounts of income and expenses to the central administration, and apart from a fixed salary to the vassal the entire surplus went to the crown. This was the most advantageous arrangement for the crown. There was also a form of enfeoffment which involved the vassal paying a fixed yearly impost to the crown, retaining the remainder of the income to himself (forlening på afgift). Finally the enfeoffment could be free, or for service: the vassal had only to render knight service for the fief, all its income being his own. This was the most advantageous arrangement for the vassal. In the course of the sixteenth century there occurred a shift in the proportions of the types of enfeoffment to the advantage of the crown, as can be seen from the following chart:

¹⁰ Frederick I did so in an open letter of 27 Aug. 1525, and Christian III in a declaration bearing the royal seal of 12 Nov. 1542.

¹¹ The bushel hartkorn (td. htk.) is a Danish unit of measurement defined as an area of land yielding annually the equivalent of one barrel of rye or barley.

¹² It should be stressed that what follows is a presentation of some highly complex relationships which for the sake of argument have been drastically simplified. The complexity of the picture is further exacerbated by the fact that society in Denmark, as elsewhere in the sixteenth century, was undergoing significant changes, even though the ostensible organizational pattern of society was still the medieval system of estates. There is no comprehensive presentation of these developments in any of the major European languages, but for an introductory sketch see Petersen, E. Ladewig, The crisis of the Danish nobility 1580–1660 (Odense, 1967)Google Scholar, and ‘Add, Bürgertum und Gutsbesitz in Dänemark des 17. Jahrhunderts’, in Jürgen, Schneider (ed.), Wirtschaftskräfte und Wirtschaftswege: Festschrift für Hermann Kellenbenz. (Bamberg, 1978), pp. 473–92Google Scholar. See also Sven, Aage Hansen, Adelsvaeldens grundlag (Copenhagen, 1964) -with English summary, and finally Knud J. V. Jespersen, Rostjenestetaksation (above, note 8).Google Scholar

¹³ Among these developments mention should be made in particular of the international economic crises of the last quarter of the sixteenth century and the first quarter of the seventeenth, which had a serious impact on the Danish economy. There were in addition the rampant inflation of the sixteenth century and the confiscation of ecclesiastical estates at the Reformation in 1536.

¹⁴ As a result of changing economic conditions there occurred a social differentiation within each social class in the course of the sixteenth century and the first part of the seventeenth, as a consequence of which society as a whole experienced a social stratification which cut across the old class divisions (see the studies referred to in note 12). We encounter the same development all over Europe at this time.