American logistics in the Northern France campaign played a key role in the Allied invasion of northwest Europe during World War II. In the first seven weeks after D-Day, the Allied advance was slower than anticipated in the Operation Overlord plan because the well-handled and determined German opposition exploited the defensive value of the Normandy bocage country. The Northern France campaign officially commenced on 25 July, the day First United States Army began Operation Cobra, which saw the breakout from the Normandy lodgment, and ended on 14 September.
Following Operation Cobra the advance was much faster than expected, and the rapid increase in the length of the line of communications threw up unanticipated logistical challenges. The logistical plan lacked the flexibility needed to cope with the rapidly changing operational situation; the rehabilitation of railways and construction of pipelines could not keep up with the pace of the advance, and resupply by air had limited capacity. Major shortages developed, particularly of petrol, oil and lubricants (POL).
Motor transport was used as a stopgap. The Advance Section (ADSEC) organized the Red Ball Express to deliver supplies from the Normandy area, but there was a shortage of suitable vehicles owing to political interference and production difficulties. The tardy delivery of vehicles adversely affected the training of motor transport unit personnel. As with many other service units, the European Theater of Operations (ETO) was compelled to accept partially trained units in the hope they would be able to complete their training in the UK. Approval for additional relief drivers was also slow, and the US Army's racial segregation complicated personnel assignment. The cost of inadequate training of truck drivers was paid in avoidable damage to vehicles through accidents and poor maintenance.
At critical junctures in the campaign, senior American commanders subordinated logistical imperatives to operational opportunities. Two decisions in particular had long-term and far-reaching effects. The decision to abandon plans to develop the ports of Brittany left only the Normandy beaches and the port of Cherbourg for the maintenance of the American forces. The subsequent decision to continue the pursuit of the defeated German forces beyond the Seine led to the attrition of equipment, failure to establish a proper supply depot system, neglect of the development of ports, inadequate stockpiles in forward areas, and a shortage of POL and ammunition as increased German resistance stalled the American advance. While the logistical system had facilitated a great victory, these factors would be keenly felt in the fighting in the months to come.
Background
After the American entry into World War II in December 1941, the European Theater of Operations, United States Army (ETOUSA) was formed, with a Services of Supply (SOS) organization under Major General John C. H. Lee beginning in May 1942. General Dwight D. Eisenhower became the Supreme Commander, Allied Expeditionary Force, on 16 January 1944, and ETOUSA and SOS were combined into a single headquarters, which was increasingly referred to as the Communications Zone (COMZ), although this did not become official until 7 June. To support Operation Overlord, the invasion of Normandy, COMZ activated two subordinate headquarters, the Forward Echelon, Communications Zone (FECOMZ), under Brigadier General Harry B. Vaughan, with Colonel Frank M. Albrecht as his chief of staff, and the Advance Section (ADSEC), under the command of Colonel Ewart G. Plank. ADSEC would take over the operation of base areas, supply dumps and communications from the First Army as it moved forward. In the initial stages of Overlord, ADSEC would be attached to the First Army.