German Intelligence Successes in World War II

Sergeant Vogel barked out a quick order over the radio: "1st Company, withdraw immediately!" The drab French Char B tanks complied. Now, sergeants do not typically command French tank companies—especially not German Army sergeants.

But that is who Vogel was, a lowly sergeant with a radio and passable French. His orders for the French tanks to withdraw was a ruse the Germans pulled again and again in both Poland and France in the early years of World War II. It epitomized the German focus on intelligence at the tactical and operational level.

Nazi Germany lost the war, and the world is much better for it. But the Germans fought hard and gave their opponents fits, including in the field of intelligence. Those successes do not include anything like the dramatic code breaking that the Allies achieved against the Axis, but there were achievements nonetheless.

Like the Allies, the Germans’ greatest successes were in the field of communications intelligence. Germany set up listening posts in Spain and traded cipher information with Japan, Italy, Finland, and Hungary. Germany did not ignore code breaking. It broke the ciphers of every nation except the Soviet Union. German lieutenant general (field marshal after the spring of 1941) Erwin Rommel’s best information source in North Africa was the American military attaché in Cairo. Rommel regularly read his detailed reports on British forces, thanks to German code breaking. Code breaking also enabled the German Navy to know the positions of British ships prior to Germany’s invasion of Norway in 1940.

Germany also had the ability to intercept high-level communications. A German radio intelligence post in the Netherlands monitored and descrambled the radio-telephone conversations between American President Franklin D. Roosevelt and British Prime Minister Winston Churchill in real time. The exchanges were taped and translated for Germany’s Fuhrer, Adolf Hitler, but the effort yielded very little intelligence. Similar types of communications eavesdropping gave Hitler intelligence on Czech intentions in 1938 and those of the British, French, and Polish a year later.

Even intercepting plain text messages and radio communications led to intelligence successes. The Germans focused on low-level nets, a strategy that "contributed enormously to German tactical and operational success," according to author David Kahn, known for his work on German military intelligence. They prided themselves in rapidly exploiting intercepted communications for commanders so that it was actionable intelligence.

Low-level nets rarely spell out exactly what the enemy is going to do on a large scale. The Germans excelled in the field of traffic analysis. Through systemic interception, detailed record keeping, close study, and fusion with other intelligence sources, the predictions of German traffic analysts were right about 90% of the time (The Germans checked their predictions retroactively to arrive at this percentage.)

It achieved much of this not in some office far removed from the field of battle but right on the front. Rommel’s second best intelligence source in the North Africa campaign was his radio intercept company, the 621st. Like any other unit in this theatre, the 621st suffered from thirst, poor rations, the heat, and most especially, the enemy. This small unit predicted British offenses and provided Rommel with much information on the British order of battle. The 621st was so successful that some say the Allies targeted it for destruction. A July 1942 raid by Australian infantry and tanks did just that, decimating the 621st.

Allied bombers conducted radio checks prior to missions. The Germans monitored these transmissions and Allied efforts at deception and disguise did not fool them. The Germans detected the 1943 raid on oil refineries at Ploesti, Romania, in this fashion. Axis air defenses were ready for the American B-24 Liberators and shot down a third of them.

Air reconnaissance was also important to the Germans. It was not a single mission; rather, it was regular flights over the target, building up what is now called a "pattern of life." Such systematic efforts paid off until Allied air superiority put an end to German air reconnaissance towards the end of the war.

But the early part of the war was a different story. A German Ju-88 flew over Alexandria, Egypt, in 1942, at 37,500 feet. No British fighter could reach it at that altitude and the flak was just wasting its time. The Ju-88 returned with photographs showing a buildup of British merchant shipping. When this shipping tried to resupply Malta, the Germans were ready and only 10% of the freighters made it. Air reconnaissance also detected Russian efforts to build a dam over an inlet across the Sea of Azov prior to their attack. German bombing destroyed the dam and delayed the Russian offensive by several months.

Germany also focused on battlefield reconnaissance. Careful observations over time built up excellent indications of Allied intentions. If the Soviets wore field caps, they were on the defensive. Helmets indicated that an offensive was in the works. Such simple indicators allowed the German 102nd Infantry Division to anticipate and repel a Russian attack in November 1942.

German spies mostly failed, but a few did succeed. One passed along the blueprints to the Norden bombsight in 1937. The Germans then built a copy and made improvements to their own sights based on what they learned about the Norden. Another spy visited American war factories, including Edgewood arsenal, thanks to deep cover and fast talking. Germany managed to infiltrate spies into New York City as late as 1944, although those agents weren’t what you would call effective. The daring mission had a U-boat dropping off the infiltrators in Maine on a snowy night. Once in the big city, the spies quickly forgot their mission and used their funds for chasing women and partying instead.

Germany used many open sources. Before the war, its military attaches were an excellent resource. Its attaché in England easily answered German general Heinz Guderian’s query on communications between British infantry and armor. Allied newspapers and radio broadcasts were worth paying attention to. Sometimes the Germans had to go to great lengths to get newspapers, trading with Dutch and Portuguese fisherman to get American and English ones at times. Sometimes the Allied press leaked information, such as the details of American landing craft.
The Germans interrogated prisoners mostly to build up their enemy order of battle. With their thorough methods, even seemingly innocent documents such as ration cards gave away a prisoner’s unit.

German field marshal Erich von Manstein used intelligence better than any German commander. He listened carefully to his intelligence analysts in his early 1943 campaign against the Russians. He hit the Russians where they were weak and sent them reeling.

But Manstein’s use of intelligence was the exception, not the norm. Good intelligence brings in information about the enemy’s capabilities and intentions. But in a losing war, it brings in information that commanders and political leaders do not want to hear, let alone heed. That certainly proved to be the case with German intelligence in World War Two.

This is the first of two parts on Axis intel successes in World War II. Part 2 explores Japanese intelligence successes of the Second World War.

About the Author
Hans Johnson is a freelance writer who lives in Florida.