Colonel Max Hermann Bauer (31 January 1869 – 6 May 1929) was a German General Staff officer and artillery expert in the First World War. As a protege of Erich Ludendorff he was placed in charge of the German Army's munition supply by the latter in 1916. In this role he played a leading role in the Hindenburg Programme and the High Command's political machinations. Later Bauer was a military and industrial adviser to President Chiang Kai-Shek of Nationalist China.

Bauer was born in Quedlinburg. He began to study medicine in Berlin, but then enlisted as an officer candidate in Foot Artillery Regiment 2 (heavy artillery) in 1888. The following year he attended the Kriegs-Schule in Hanover and then was commissioned. After regimental service, in 1898 he was appointed Adjutant to the Artillerie Prüfungskommission (Artillery Testing Commission). In 1902 he took command of a battery as a captain. An observer of the Russo-Japanese War (1904-05), he was impressed by how Japanese 28 cm mortars demolished Russian forts. When he returned in 1905 he joined the fortress section of the General Staff as their artillery expert, which made him conversant with the leaders of German industry, science, and engineering. Unable to obtain authorization to develop a new heavy mortar, he ordered one from Krupp nonetheless. When the War Ministry learned that a prototype was completed they wanted Bauer dismissed, but the firing tests were so impressive that further development was authorized in 1911. Meanwhile, in 1908 he moved into the mobilization section of the Staff directed by Erich Ludendorff — they became staunch friends. Ludendorff regarded him as the “smartest officer in the army”. In the following year Bauer was appointed as a General Staff Officer, remarkable because he had not had the customary specialized schooling. Helped by his contacts in industry, he studied how the German economy would function during a European war.

When the war came Major Bauer was posted to the Operations Section of Oberste Heeresleitung (OHL, Supreme Army Command) as head of Section II, which was responsible for heavy artillery, mortars, and fortresses. Earlier in 1914, the first of the Krupp 42cm mortars, nicknamed "Big Bertha", and its concrete-piercing shells were ready. They smashed the forts in Belgium and northern France. In 1915 the huge guns forced the surrender of the formidable Russian fortifications in Poland, like Przemyśl, before dealing with the Serbian strongholds at Belgrade. For developing the mortars Bauer was awarded the Pour le Mérite and an honorary doctorate from the University of Berlin. (In 1918 he received the Oak Leaves for his Pour le Mérite. During the war he was awarded 25 German and foreign medals.)

Before the war he had worked with the chemist Fritz Haber to transform nitrogen from the air into explosive precursors, which let the Germans make war despite the Naval blockade of Germany preventing continued imports of supplies of nitrates that had come from Chile before the war. When the adversaries deadlocked in their trenches along the Western Front, Haber suggested that they could break through by releasing a cloud of poisonous chlorine gas, which is heavier than air. Bauer provided funds and scientists already in the army. Bauer, Haber and Duisberg, the head of the chemical cartel, and their horses were poisoned at the first field test; all were invalided for days. He was present at the first attack, which cleared the defenders out of miles of trenches defending the city of Ypres, but was "heartbroken" because Supreme Commander Erich von Falkenhayn had mounted only a diversionary attack, divulging their top-secret for almost no gain. Bauer continued to support the development of new gases, tactics to use them effectively despite protective masks, and Haber's mobilization of scientists for the war effort.

Section II of OHL Supreme Army Command carefully evaluated how their weapons performed on active service. For instance, in 1916 they produced a modified field gun that could be elevated to 40 degrees, compared to its former 16 degrees, and their light howitzer's range was increased 43 percent to 10,000 m (11,000 yd). They formed a unit to develop assault tactics using stormtroopers. Their first tank, introduced in May 1917, was too large and unwieldy, few were produced, so they had to use captured enemy tanks. Krupp and Daimler designed a light tank, but production was not authorized until French light tanks showed their value, consequently they could not be available until April 1919.

Bauer strongly opposed Falkenhayn's plan to attack Verdun in 1916 along a narrow front on the right bank of the Meuse, because their flank would be vulnerable to French artillery on the left bank—he was spot-on; before long they had to attack the left bank as well. While arranging artillery support before the attack he stayed at Fifth Army headquarters where he became a fast friend of its commander, Crown Prince Wilhelm; they kept in touch thereafter. In the first salvo of the attack a 42 cm shell struck Fort Douaumont, a key to the defense. It did not penetrate the reinforced concrete and sand layers: the Verdun forts were stouter than any the mortars had fired on hitherto. Later that year Bauer was dismayed by Falkenhayn's insistence along the Somme front on packing infantry into the foremost trenches to repel the attacks, where they were chewed-up by the Entente's artillery preparations. Bauer decided that Falkenhayn must be replaced by his friend Ludendorff, who had displayed virtuosity on the Eastern Front. Supported by junior officers at OHL he tirelessly lobbied the highest echelons of the army and government against his superior, with criticisms of Falkenhayn like "...his decisions were half measures and he wavered even over these." Falkenhayn was replaced on 29 August 1916 by Field Marshal Paul von Hindenburg as Chief of Staff with First Quartermaster General Ludendorff as his associate. To Bauer this was his greatest victory.

The new commanders resolved to wage total war. OHL Supreme Army Command was reorganized, Bauer's Section II was responsible for heavy artillery, mortars and fortresses. Bauer set highly optimistic goals for weapon production, for instance tripling machine gun output, in what became known as the Hindenburg Program. His industrialist friends welcomed the orders but needed more workers. Skilled men were released from the armed forces and a bill making most men and women subject to national service was proposed to the Reichstag, which rejected the most extreme measures, like shutting the universities except for their medical schools. Compelling women to work was unnecessary, because already more were looking than there were jobs. The bill that finally passed was almost useless. Soon Bauer had a staff officer for propaganda and another stationed in Berlin for political liaison. Despite their exertions, "Unable to control labour and unwilling to control industry, the army failed miserably...."

Lieutenant General von Höhn's draft of a manual describing defense in depth was rewritten by Bauer and Captain Geyer. The crux was that any attackers who penetrated a lightly manned front line would be destroyed by counterattacks. Defense in depth became German Army doctrine through the Second World War.