Final answer:
At the onset of World War I, civilians and soldiers alike believed the war would be brief and expected soldiers to return home by Christmas.
Step-by-step explanation:
At the beginning of World War I, most citizens thought their soldiers would be home by Christmas. There was a widespread belief across European countries that the conflict would be short-lived. This belief was not limited to Germany; countries like France also shared this expectation. The early confidence in a swift war was partly due to nationalistic fervor and a lack of experience with prolonged modern warfare among the young soldiers who eagerly enlisted. However, as the war continued, the initial enthusiasm faded in the face of the reality of trench warfare, and the war extended far beyond that first Christmas.