The first five weeks of Operation Barbarossa were a smashing success. The Wehrmacht encircled and destroyed hundreds of Soviet divisions, and had taken almost a million prisoners. At the end of June, the last organized Soviet mechanized corps were destroyed at the Battle of Brody in the largest tank battle to date. The Soviet KV-1s and T-34s were a nasty surprise to panzertruppen in the outmatched PzIIIs, Pz38s, and PzIVs, but Soviet self inflicted logistics, command and control issues, the vaunted 88s flak guns, and Luftwaffe induced supply problems evened the odds. By mid-July 1941, both Army Groups North and Center were within striking distance of their final objectives, Leningrad and Moscow.

But all was not going according to plan. For every dozen divisions the Germans destroyed, Stalin put 14 ill trained, ill led divisions back into the line: just enough to slow them down. Supplies and maintenance were becoming an issue: Most German divisions were at 70% strength and the Panzer and motorized divisions at 50%. Army Group Center’s forward supply dumps were 750km from nearest railhead. Army Group South, separated from the other army groups by the Pripyat Marshes faced much more effective delaying tactics on the Ukrainian Steppe by the Soviets under Marshal Budyonny (and his Political Officer Nikita Khrushchev). Furthermore, the bypassed Fifth Army in the Pripyat Marshes threatened AG South’s flank, and many divisions were forced from the advance to contain them.

On 19 July 1941, Hitler issued Directive 33, which was a very vague order to capture Leningrad, Moscow, the industrial area around Kharkov, encircle and destroy the Soviets facing AG South, and clear the Pripyat. The German High Command, particularly General Halder the chief of the OKW, disagreed with Hitler’s focus on the Red Army in the South. It was clear even at this early stage of the campaign that unlike in France, the army was not the center of gravity. He pushed for continued attack to seize Moscow at the expense of Leningrad, the Ukraine, the much needed reorganization and refit of Army Group Center, and the destruction of the Red Army in the South. Unlike Napoleon’s invasion 130 years before, Moscow was much more important to Stalin than to Tsar Alexander. Moscow was the cultural, industrial, administrative, and communications center for the Soviet Union, the Communist Party, and Stalin’s regime. Virtually all rail traffic west of the Urals went through Moscow. On 26 July 1941, there just 19 under strength Soviet divisions between Army Group Center and Moscow. Finally, Halder knew Stalin would defend it with everything he had left, which incidentally would satisfy Hitler’s fetish for destroying the Red Army.

The ill Hitler disagreed. The Soviet armaments and tank factories were in the south and that’s where the most effective resistance by the Red Army was. They had to be crushed. Moreover, the German economy and Wehrmacht were desperate for oil, which could only be obtained in quantity from the Caucuses. On 27 July Hitler issued Supplement 1 to Directive 33, which ordered AG Center to clear the Pripyat marshes. Even worse, Supplement 1 stripped Army Group Center of its two Panzer Groups: the 3rd to the north to isolate Leningrad, and the 2nd south to seize Kharkov. Those troops would not be able to participate in the attack on Moscow until September, at which time they’d be even more in need of a respite. Moscow would have another month to prepare its defenses.