Operation Rankin

In contingency planning for the European Theater of Operations in World War II, the Chief of Staff, Supreme Allied Commander (COSSAC) had prepared three variants (Cases A-C) of Operation RANKIN. RANKIN was defined as a sudden change in the strength and determination of Germany. In hindsight, these have become classic studies of contingency planning for dealing with unexpected ends of wars. An appropriate version of RANKIN Case C, for example, could have been very useful when the army of Iraq collapsed in the Iraq War.

Cases A and B dealt with situations in which the Germans still fought, but weakened considerably. The requirement, therefore, was to land on the continent as quickly as possible, and defeat Germany from there. Case C dealt with a cessation of resistance, so the aim was to occupy as rapidly as possible appropriate areas from which to take steps to enforce the terms of unconditional surrender laid down by the allied governments.

RANKIN Case A

Case A dealt with the situation of "substantial weakening of the strength and morale of the German armed forces" to the extent that a successful assault could be made by Anglo-American forces before the planned major invasion of Western Europe.

If this took place before the end of 1943, no action was feasible unless it was clear Germany was close to collapse, and substantial naval resources were available. If the contingency took place after January 1944, the resources building up for OVERLORD could be used against weak opposition, and, after March, against stronger resistance. It was judged feasible to carry out Case A after January 1944, against the Cotentin Peninsula rather than Normandy, as long as the port of Cherbourg could be seized within 48 hours. Diversionary invasions might be needed in the Pas de Calais and in Southern France; this was essentially a modified OVERLORD.

RANKIN Case B

This dealt with the contingency of German withdrawal from occupied countries, most likely Norway and France. Western FRANCE and NORWAY. "In this case, it was necessary, for political as well as strategic reasons, to occupy the areas vacated, but it was important that the main forces of the Allies should not thereby be tied down far from the eventual centre of action."

Different actions would be required for the two areas. For Norway, the goal would be establishing air and radar bases to protect the supply route to the Soviet Union, and to block German breakouts from the Baltic sea. This could be done with one brigade in northern Norway and one division in southern Norwa.

If Germany withdrew from France, it would probably begin in Bordeaux and the Western ports, with the Pas de Calais the last area to be evacuated. One brigade each was assumed needed for Bordeaux, Brest and Nantes, to prepare them from reinforcements coming directly from the United States. The main Forcible entry at Cherbourg would be by U.S. troops while British troop[s would take Havre and Rouen.

"From these bases, the Allies would establish a line along the SOMME from which to press North-Eastwards through the PAS DE CALAIS to BELGIUM, opening up ports as they proceeded and establishing airfields from which the advance could be covered and the attack on GERMANY itself concentrated. At the same time, MEDITERRANEAN forces would be required to occupy MARSEILLES and TOULON, and to move Northwards thence in LYONS and VICHY."

RANKIN Case C

Case C dealt with possibilities such as a sudden surrender, or at least cessation of organized resistance. Had the Unconditional Surrender policy not been in effect and the July 20th, 1944 plot against Adolf Hitler succeeded, Case C might have been very relevant. It still could have applied if the plotters did surrender, perhaps with understandings about some authority.

The Case targeted the initial areas to come under control as the Jutland Peninsulal; the ports of Bremen, Hamburg and Kiel; and the large towns of the Ruhr and Rhine Valleys. Using these as bases, the Allies would then occupy the entire Rhine and Ruhr Valleys, and move into Denmark, Schleswig and Holstein. Air bases in these areas would be sufficient to establish air supremacy while disarming the rest og Germany.

In parallel, selected ports on the European coast would be opened, and the capital cities of the occupied countries brought under control. Similar processes would be carried out in Norway and the Mediterranean.

"It was estimated that 24 divisions would be required for the primary areas of occupation: 7 for DENMARK and North-West GERMANY, 6 for the RUHR and 11 for the RHINE valley. Other troops—non-field force formations wherever possible—would be required in support of the various national contingents charged primarily with the rehabilitation of their respective liberated countries."