Wladimir Rudolf Karl Freiherr Giesl von Gieslingen (18 February 1860 – 20 April 1936) was an Austro-Hungarian general and diplomat during World War I, most famous for delivering the ultimatum to the Serbian government during the July Crisis of 1914.

Born in Fünfkirchen (now Pécs) on 18 February 1860 into an officer's family as the youngest son of Heinrich Karl Giesl von Gieslingen [de] (1821–1906), an Austro-Hungarian general who had taken part in the wars of 1848–1849.

As the Serbian government did not accept all the points, Baron Giesl von Gieslingen declared that diplomatic relations were broken off and left on a train half an hour later.

Upon his return to Vienna, Baron Giesl von Gieslingen was appointed to be a liaison officer of the Foreign Ministry at the Army Headquarters and promoted to general of the cavalry in August 1914.

[4] His memoirs, compiled and published by Eduard von Steinitz, throw interesting light on Balkan conditions before the war and add some details concerning the final diplomatic rupture between Austria-Hungary and Serbia in 1914.