Final answer:
The Schlieffen Plan aimed to quickly defeat France by invading Belgium, before Russia could fully mobilize, allowing German forces to subsequently focus on the Eastern Front. Belgian resistance and faster Russian mobilization interrupted the plan's execution, resulting in a protracted two-front war for Germany.
Step-by-step explanation:
The Schlieffen Plan was supposed to support Kaiser Wilhelm II's ambitious goal of quickly defeating France and then turning East to face Russia in a swift campaign. According to the plan, Germany intended to bypass the heavily fortified Franco-German border by invading France through Belgium, which was less defended, thus ensuring an accelerated attack towards Paris.
The plan was predicated on the belief that Russia would take a long time to mobilize its army, thereby giving Germany the advantage of defeating France first. German commanders believed France could be rapidly defeated, similar to the Franco-Prussian War, and then the troops could be redeployed East, utilizing the German rail system to meet the Russian forces on the Eastern Front.
However, the expected quick success did not materialize. Belgium's resistance, combined with the quicker-than-anticipated Russian mobilization, foiled the timeline of the Schlieffen Plan, leading to a prolonged conflict on both the Western and Eastern fronts.
The stalling of the German advance in Belgium allowed the French to regroup and contribute to the failure of the German Schlieffen Plan. The Battle of Tannenberg saw German troops diverted to the East to counter Russian forces in East Prussia, leading to a significant Russian defeat, but at the cost of weakening German efforts in the West.