[2] Leeb was a highly decorated officer in World War I and was awarded the Military Order of Max Joseph which granted him the title of nobility.

During Operation Barbarossa—the invasion of the Soviet Union—Leeb commanded Army Group North, which advanced through the Baltic States towards Leningrad (present day St. Petersburg), eventually laying siege to the city.

He was convicted of transmitting the Barbarossa Decree and its criminal application by subordinate units and sentenced to three years' imprisonment time served and was therefore released after the trial concluded.

[6] During Operation Barbarossa, the invasion of the Soviet Union, Leeb was given command of Army Group North to invade the Baltic states and to capture Leningrad.

Leeb was one of more than 200 senior officers who on 30 March 1941 attended a speech in which Hitler laid out his plans for an ideological war of annihilation (Vernichtungskrieg) against the Soviet Union.

[9] In late June and early July 1941, Franz von Roques, the Rear Area commander, informed Leeb of the massacres of Jews by Einsatzgruppe A, Lithuanian auxiliaries and the men of the 16th Army outside Kaunas.

[10] In early July, General Rudolf Schmundt, Hitler's aide responsible for the disbursing secret extra-legal payments from the Konto 5 fund, visited the headquarters of Army Group North.

He told Leeb's staff that the pogroms against and the murder of the Jews by Einsatzgruppe A were a "necessary cleaning up operation" and that "soldiers should not concern themselves with political matters".

[11] The same month, Franz Walter Stahlecker, the commander of Einsatzgruppe A, in a report to Berlin praised Army Group North for its exemplary co-operation with his men in murdering Jews in the Baltic states.

In contrast to those expectations, the marshy terrain around Lake Ilmen and fierce Red Army counterattacks prevented a quick advance.

Having received reports on the evacuation of civilians and industrial goods, Leeb and OKH believed the Red Army was preparing to abandon the city.

[17] Lacking sufficient strength for major operations, Leeb had to accept the army group might not be able to take the city but hard fighting continued along his front throughout October and November.

Leeb ordered the artillery to fire at any civilians trying to escape from the encircled city to kill them out of view of the frontline infantry.

[19] In mid-November, the army group's war diary noted the artillery was preventing civilians from approaching the German lines.

In December 1941, with the consent of 18th Army commander Georg von Küchler, SD personnel shot 240 patients in a psychiatric facility.

[21] On 15 December 1941, in the midst of the crisis of the Battle of Moscow, Leeb pulled back his forces on the northern wing to a line behind the Volkhov River without permission from OKH.

[27] Leeb was found guilty on one of four charges; he was convicted of transmitting the Barbarossa Decree and its criminal application by subordinate units.