The Totenkopf was assigned to Army Group North for Operation Barbarossa, the plan for the invasion of the Soviet Union. On 22 June 1941, Barbarossa began and the Totenkopf began its advance. Initially, Army Group North did not assign the Totenkopf any real frontline combat, but it was soon thrown into action. Meierdrees, as a StuG platoon commander, led his assault guns aggressively and was soon building a reputation as a highly skilled armour commander. Meierdrees' unit saw heavy action during the assault towards Leningrad, the objective of Army Group North. By December 1941, the Germans had breached the Stalin Line and were at the gates of Leningrad.
Several strong Soviet assaults launched at the height of winter caught the exhausted Germans off guard. The Totenkopf managed to hold its section of the line near Demjansk in ferocious fighting. By early January 1942 Totenkopf's position was located in a salient which protruded into the Soviet lines. The Soviets, hoping to sever the German supply lines and encircle the forces around Demjansk, launched ferocious attacks at the flanks of the salient. During this period, Meierdrees and the remnants of the StuG Battery performed fire-brigade missions, halting all Soviet attempts.
On 15 January 1942, the Soviets launched a major attack which threatened to sever the main highway at the town of Bjakowo. Meierdress, seeing the threat, formed an ad-hoc Kampfgruppe (battle group) from his StuG battery (down to less than 100 men) and assorted engineers, SS-police troopers and Artillery reconnaissance troops which were located in and around the town. With his kampfgruppe, Meierdrees held the town against repeated assaults by much larger forces.
Heavy Soviet attacks further to the south, launched on 8 February, sliced through the flanks of the Demjansk salient, trapping Totenkopf and five other divisions, over 100,000 men, in a kessel (pocket).
The Totenkopf, exhausted from the winter fighting, was severely understrength. Meierdrees' kampfgruppe, down to only 30 men, continued to hold the line at Bjakowo, now the closest point to friendly lines. For his actions during these battles, Meierdrees was awarded the Iron Cross, first class.
In early February, the Soviets captured Bjakowo, cutting off the Totenkopf, including Meierdrees' force from the main German force, II. Armeekorps, encircled around Demyansk itself.
On February 18, Meierdress was seriously wounded. After Meierdrees' incapacitation, Totenkopf's SS-Sturmbannführer (Major) Franz Kleffner took over the command at Bjakowo. On February 19, he led the survivors in an assault which resulted in a breakthrough to the main force, an action for which Kleffner won the Knight's Cross. On 21 February, Meierdrees was flown out of the pocket in a Fieseler Fi 156 Storch.
Severely wounded, Meierdrees was sent back to an SS Field Hospital, where it was feared that he would die. By early March, his condition had stabilized. On 13 March 1942, Meierdrees was awarded the Knight's Cross in recognition of his courage and resourcefulness while encircled near Bjakowo. The SS newspaper, Das Schwarze Korps published a story on his actions.