‘Batavische constantie’

Based on archival research, this article describes the actions taken by the city government to put Amsterdam into a state of defence during 1672, the so-called Disaster Year. Particular attention is paid to the spatial consequences of these measures. In the spring of 1672, the Dutch Republic was attacked by an alliance between France, England, Cologne and Münster. The French army’s advance was eventually halted on the border of the province of Holland by dint of flooding the polders. In 1673, the tide of the war turned in the Republic’s favour, and hostilities ceased in 1674. In 1659, Amsterdam had embarked on a series of major urban expansion works between the Leidsegracht canal and the IJ inlet. On 10 June 1672, all city works were halted except those on the fortifications. Priority was given to the restoration of the city wall, which had been weakened by subsidence. Outside the wall, a free field of fire was created, and measures were taken to defend the unfortified IJ shore. The city militia was also reorganized. From June 1672, a semi-circle of low-lying polders around Amsterdam were flooded by opening sluices and breaching dykes. This was done step by step, in a form of dynamic water management that was constantly adapted to the changing circumstances in order to maximize the defensive potential and to  minimize the damage. Waterways were blocked off and defended by armed ships. Six fortifications were built on the higher access roads in the immediate vicinity of the city, often close to one of the inundation openings. These were permanently manned. The city government also arranged for the construction of outposts further away, such as in Uithoorn, which were crucial to maintaining the flooding operations. With the river Vecht acting as the first line of defence – the ‘outer wall’ of Amsterdam as it were – Muiden, Weesp, the Hinderdam and Nieuwersluis were also reinforced with fortifications. After the recapture of Naarden in 1673, the first steps were taken to return to normality and in 1674-1675 all temporary fortifications were demolished. All defensive structures disappeared from the landscape around Amsterdam. From this point of view, the spatial consequences seem to have been short-lived. However, the 1672 defence concept served as a model for all later defence lines around Amsterdam, the last one being the Stelling van Amsterdam, or Amsterdam Defence Line, in which the capital city functioned as a ‘national redoubt’. In this respect the spatial consequences of the Disaster Year cannot be underestimated.