During World War II, he served with distinction in Poland in 1939 and then on the Russian Front, commanding several tanks that were knocked out and personally leading several ad hoc attacks.

Oppeln-Bronikowski led the desperate attack of the 22nd Panzer Division on the 19th of November 1943 in an attempt to forestall the encirclement of German forces in Stalingrad.

In one particular instance, as an Oberst commanding the 100th Panzer Division at Falaise, France; he was visited at 8:15 in the morning on 11 May 1944 by Rommel, who was satisfied with the forces' defensive preparations, but said to him – You lazy stinkers, what happens if the enemy invasion begins before 8:30!

Oppeln-Bronikowski, who had gone to sleep in his now crumpled and tobacco-smelling uniform, and still had alcohol on his breath, could only reply Catastrophe and Rommel laughed.

[1] Oppeln-Bronikowski led a panzer counter-attack on the invading forces immediately after the D-Day Invasion, and was told by his commanding officer that if he did not throw the British back into the sea, the war would be lost.