Past Tense: Why the Western Allies chose Normandy, not Spain, as the invasion site for D-Day

Why didn’t the Western Allies invade France via Spain and avoid the fortified beaches on the Normandy coast?

The quickest way to victory is to invade Northern France, then liberate Belgium and cross the border into Germany proper.

There were many different factors involved, including the reality that Spain was officially neutral (albeit somewhat sympathetic toward the Third Reich).

The main military reasons why the Allies didn’t invade France via a Spanish “back door,” of course, were geography and logistics.

Keep in mind that the primary proponents of the cross-Channel attack were the American commanders, Gen. George C. Marshall and his protege, Gen. Dwight D. Eisenhower. They were of the opinion that the only way to defeat Nazi Germany was to land in France and drive directly into the Reich as quickly as the Allies’ resources would permit.

The British, on the other hand, preferred an indirect peripheral approach instead of a head-to-head confrontation in the fields of France and Belgium. That’s why they championed the Anglo-American landings in French Morocco and Algeria (Operation Torch) and the 1943 invasions of Sicily (Operation Husky) and Italy (Operations Baytown, Avalanche, and Slapstick). The British proponents of the Mediterranean campaign wanted to knock Italy out of the war. They also hoped to drive up the Italian peninsula and invade Germany through passes in the Alps, as well as liberating the Balkans before the Red Army.

Unfortunately, the southern route through the Axis’ “soft underbelly” didn’t provide the Allies with a decisive victory. The mountains and rivers of the Italian peninsula provided the Germans with favorable terrain for the defense. Also, the Americans continued to press for an invasion of France by May of 1944 and refused to commit more troops and resources to the Mediterranean theater.

Landing in Portugal and marching through Spain - not the shortest route to victory, is it?

Since the invasion of France was intended to place the Allied Expeditionary Force close to Germany’s western frontier and the vital industrial complexes of the Ruhr Valley, landing in Portugal and Spain would have been counterproductive. Even if Generalissimo Francisco Franco had acquiesced to an Allied landing and dropped all pretense of neutrality, the Allied forces would still be hundreds of miles away from their main objectives. Without air support from the British Isles, the invaders would have had to build airfields and set up assembly areas close to the Pyrenees Mountains, the range which separates Spain and France. And, as the Allies discovered when they invaded Italy, attacking an enemy via rough mountainous terrain that can be easily defended is no picnic.

Not only would an invasion of France through the Iberian peninsula have stretched Allied supply lines and caused the war to drag on until 1946 (unless the Americans dropped the Bomb on Berlin in 1945), it also would have allowed the Soviets to overrun all of Germany and claim that the Soviet Union won the war on its own