Final answer:
The German invasion of Poland in 1939 exemplified the 'blitzkrieg' military strategy of swift and coordinated attacks by air and ground forces, resulting in the rapid defeat of Polish defenses.
Step-by-step explanation:
The German invasion of Poland in 1939 was a demonstration of a military strategy known as blitzkrieg, which translates to “lightning war.” This strategy involved a coordinated, rapid series of attacks by air and ground forces aiming for a quick and decisive victory. Blitzkrieg sought to avoid the prolonged trench warfare of World War I by utilizing tanks, planes, and motorized infantry to concentrate forces, break enemy lines, and cause chaos behind enemy defenses. In Poland, the effectiveness of blitzkrieg was evident; Germany's use of overwhelming air power and fast-moving armored divisions resulted in the encirclement and swift defeat of the Polish army. Despite a strong initial resistance, Poland fell to Nazi Germany on September 27, 1939, after four weeks of intense warfare.