Military dimensions to small- and medium-scale Irish topographic mapping during the twentieth century

Abstract

This article traces the development of military mapping in Ireland during the early and middle twentieth century. Particular attention is given to the evolution of precise systems for the identification of location, the use of maps for training and for military manoeuvres, the use of maps during the 1920-21 War of Independence, and the development of 1:20,000 scale maps for military requirements. Artillery training maps at this scale were produced for the British Army during World War 1, and the 1:20,000 scale was again explored by the Irish military during the late 1920s and in the 1930s. Features of these maps were the use of closely spaced contours, a grid system to specify locations, and partial or complete metrication of heights and distances. Proposals for a 1:20,000 scale map series made by the Irish authorities were followed by subsequent technical assessment.  Several experimental and innovative map sheets were published, possibly partly as a result of military training exercises, during the 1930s. Their modern design and influence from British and French cartographic traditions has attracted attention. However, the impact of World War II curtailed the further development of the 1:20,000 series. The postwar focus was on modernising the triangulation framework, creating an appropriate Irish grid and then re-organising map scales to ‘rounded’ numbers suitable for the metric system and comparable to most other European countries. The survey organisations in both Dublin and Belfast participated in these developments, but it was in Northern Ireland that a new phase of military mapping was precipitated by the ‘Troubles’ that began in the late 1960s and which lasted some three decades. That mapping included a special 1:20,000 map series that was never formally published and, for the main urban centres, ‘religious areas’ maps together with specially adapted 1:2500 maps.