attack on German parachutists. If that was not possible, the division was to cordon off and immobilise any German invasion effort until relieved by forces capable of launching a major counter-attack to defeat the Germans. As 1939 turned into 1940, the division became caught up in an effort to address manpower shortages among the BEF's rear-echelon units. More men were needed to work along the line of communication, and the army had estimated that by mid-1940 it would need at least 60,000 pioneers. The lack of such men had taxed the Royal Engineers and Auxiliary Military Pioneer Corps, and had also impacted frontline units that had to divert men from training to help construct defensive positions along the Franco-Belgian border. To address this issue, it was decided to deploy untrained territorial units as an unskilled workforce, thereby alleviating the strain on the existing pioneer units and freeing up regular units to complete their training. As a result, the decision was made to deploy the 12th (Eastern), 23rd (Northumbrian), and the 46th Infantry Divisions to France. Each division would leave their heavy equipment and most of their logistical, administrative, and support units behind. In total, the elements of the three divisions transported to France amounted to 18,347 men. The 46th Division was deployed to Brittany. The 137th Brigade was sent to aid in the unloading of supplies at Saint-Nazaire and Nantes, as well as helping construct railway sidings in that area. The other two brigades were deployed to Rennes to assist in railway construction and aid the transportation of ammunition supplies. The intent was that by August their job would be completed and they could return to the United Kingdom to resume training before being redeployed to France as front-line soldiers. The Army believed that this diversion from guard duty would also raise morale. Lionel Ellis, the author of the British official history of the BEF in France, wrote that while the divisions "were neither fully trained nor equipped for fighting ... a balanced programme of training was carried out so far as time permitted". Historian Tim Lynch commented the deployment also had a political dimension, allowing "British politicians to tell their French counterparts that Britain had supplied three more infantry divisions towards the promised nineteen by the end of the year." General Edmund Ironside, chief of the imperial general staff, was opposed to such a use of these divisions. He