Final answer:
Austria-Hungary was cautious in declaring war on Russia due to the need to align with Germany's military preparations and strategic timeline, which involved quickly defeating France under the Schlieffen Plan before turning to the Eastern Front. Ensuring Germany's readiness and preventing immediate military defeat and internal turmoil within Austria-Hungary were key reasons for the delay.
Step-by-step explanation:
Austria-Hungary's delay in declaring war on Russia was influenced by a complex interplay of diplomatic relationships, military strategies, and political calculations during the prelude to World War I. After issuing an ultimatum to Serbia, Austria-Hungary, emboldened by Germany's "blank check" of support, declared war on Serbia. Germany expected Austria-Hungary to act swiftly, but they were cautious, aware of the risks of Russian involvement. Germany's own strategic plan, the Schlieffen Plan, assumed a slow Russian mobilization, allowing Germany to first defeat France by advancing through Belgium before turning eastward to support Austria-Hungary against Russia. This plan relied on assumptions that were crucial to the timing of declarations of war and mobilizations.
For Austria-Hungary, a hasty war declaration on Russia could result in an immediate military defeat, spurring internal unrest and emboldening Balkan rivals. It was imperative to ensure that Germany was fully prepared to back them, and that the German military's schedule was aligned with the Schlieffen Plan. Crucially, the hope was to incapacitate France rapidly, enabling the redeployment of German forces to aid Austria-Hungary before Russia could fully mobilize. The complex network of alliances and geopolitical interests made these initial weeks critical to the success of the Central Powers' overall war strategy.