Question: Alfred von Schlieffen was instrumental in devising the plan that was used after which event?

Context paragraphs:
Weltreise: Weltreise (The World Trip) is the second studio album by German electronical project Schiller by Christopher von Deylen and Mirko von Schlieffen.  The album was internationally marketed as Voyage.  It became a surprise hit, staying on the top position of the German longplay charts for four consecutive weeks.  The album featured Kim Sanders and Peter Heppner as guest singers, with voice actors Otto Sander, Benjamin Völz and Franziska Pigulla adding spoken words passages.

Gefühle: "Gefühle" (German: "Feelings" ) is a song by German recording artist Yvonne Catterfeld, recorded for her debut studio album "Meine Welt" (2003).  It was written by Klaus Hirschburger, Mirko von Schlieffen, Achim Jannsen, and Manfred Thiers, while production was helmed by von Schlieffen, Jannsen, and Thiers.  A mid-tempo ballad, the song was selected as the third single to be lifted from "Meine Welt" (2003).

SM-Trax: SM-Trax is an electronic duo from Germany consisting of producers Stefan Grunwald and Mirko von Schlieffen.  In mid-1999 they went to #1 on the Hot Dance Music/Club Play chart with "Got the Groove", released on Groovilicious Records.

Margot von Schlieffen: Margot von Schlieffen (born 1930) is a German former film editor.  She worked on thirty five films and television series between 1952 and 1995.

Alfred von Schlieffen: Alfred Graf von Schlieffen, mostly called Count Schlieffen (] ; 28 February 1833 – 4 January 1913) was a German field marshal and strategist who served as Chief of the Imperial German General Staff from 1891 to 1906.  His name lived on in the 1905–06 'Schlieffen Plan', then "Aufmarsch I", a deployment plan and operational guide for a decisive initial offensive operation/campaign in a one-front war against the French Third Republic.

Martin Ernst von Schlieffen: Martin Ernst von Schlieffen (30 October 1732 in Pudenzig, Pomerania – 15 February 1825 near Heiligenrode) was a German general, politician, writer and garden architect.

Schlieffen Plan: The Schlieffen Plan (German: "Schlieffen-Plan" , ] ) was the name given after World War I to the thinking behind the German invasion of France and Belgium on 4 August 1914.  Field Marshal Alfred von Schlieffen, the Chief of the Imperial Army German General Staff from 1891 to 1906, devised a deployment plan for a war-winning offensive, in a one-front war against the French Third Republic from 1905–06.  After the war, the German official historians of the "Reichsarchiv" and other writers, described the plan as a blueprint for victory.  German historians claimed that the plan had been ruined by "Generaloberst" (Colonel-General) Helmuth von Moltke the Younger, the Commander-in-Chief of the German army after Schlieffen retired in 1906, who was dismissed after the First Battle of the Marne (5–12 September 1914).

Attention!: Attention!  is the third studio album by German recording artist Alexander Klaws.  It was released by Sony BMG on Hansa Records on March 10, 2006 in German-speaking Europe.  Recorded after a short-living hiatus, it marked a departure from Klaws' previous work with "Deutschland sucht den Superstar" judge and musical mentor Dieter Bohlen, who gained no credit on the record.  Instead, the album features a wider range of producers, including Terri Bjerre, David Stenmarck, Sandi Strmljan, Thorsten Brötzmann, Ivo Moring, and Mirko von Schlieffen.

Schiller (band): Schiller is a German electronic musician, who rose to fame in 1998 and named after the German poet and dramatist Friedrich Schiller.  Originally it was a duo consisting of Christopher von Deylen and Mirko von Schlieffen.  Around 2001 or 2002, von Schlieffen left the band, leaving von Deylen the sole member.

Alfred von Ingelheim's Dramatic Life: Alfred von Ingelheim's Dramatic Life (German: Alfred von Ingelheims Lebensdrama) is a 1921 German silent film directed by Erik Lund and starring Bruno Kastner, Maria Zelenka and Hanni Weisse.

Supporting paragraphs: Alfred von Schlieffen Schlieffen Plan
Answer: World War I