The plan and its implementation both remain controversial. While Moltke's modifications certainly played their part in its failure, the plan did also presume a slow Russian mobilisation (Russia mobilised much faster than expected in 1914), and also called for the violation of the neutrality of Belgium (which in turn guaranteed the United Kingdom would be an enemy in 1914).
The above occurred in all Harry Turtledove timelines with a Point of Divergence after 1914. It also occurred in Southern Victory, although the genesis of the plan had a different in-universe explanation. The Plan is immediately germane to the following works.
Schlieffen Plan in Curious NotionsEdit
In the alternate designated as 3477 by Crosstime Traffic, the Russian mobilization of 1914 was indeed as slow as the Schlieffen Plan had presumed that it would be. Therefore, Germany was able to defeat France, Britain and Russia in a brief war, Germany's first step to global domination by the mid 20th century.
Schlieffen Plan in Southern VictoryEdit
The genesis of the Schlieffen Plan came during Alfred von Schlieffen's time as a military attaché in the United States. While observing the Second Mexican War, Schlieffen became curious about Robert E. Lee's 1862 invasion of Pennsylvania, the campaign that ultimately won the War of Secession for the Confederate States. Schlieffen was particularly intrigued by the fact that Lee hadn't directly targeted Philadelphia, but seemed to appoach it indirectly, which effectively bottlenecked Union troops.
Ultimately, the Schlieffen Plan did not succeed in shortening the war of 1914, resulting in a Great War drawn out over three years.
Despite his advanced age, General Alfred von Schlieffen personally oversaw the implementation of his plan for two-front war in 1914, leading a strong right-wing advance through Belgium and France, despite the surprisingly quick invasion from Russia. France and Britain immediately sued for peace, and Russia was in turn defeated.
Schlieffen Plan in The War That Came EarlyEdit
When the Second World War broke out in October 1938, Germany turned to a modified version of the Schlieffen Plan, which again launched a circuitous attack into France through Belgium. While the drive was probably more successful than the drive of 1914, it still came to the same halt on the banks of the Marne River in April 1939.