The Kapp Putsch — or more accurately the Kapp-Lüttwitz Putsch —was an attempt to overthrow the Weimar Republic, based in opposition to the imposed Treaty of Versailles at the end of World War I. It was branded right-wing, monarchist and reactionary afterwards.
In early 1919, the strength of the Reichswehr, the regular army, was estimated at 350,000. There were in addition in excess of 250,000 men enlisted in the various Freikorps. Under the terms of the Versailles Treaty, Germany was required to reduce its armed forces to a maximum of 100,000. Freikorps units were therefore expected to be disbanded.
In March 1920 orders were issued for the disbandment of the Marinebrigade Ehrhardt. Its leaders were determined to resist dissolution and appealed to General Walther von Lüttwitz, commander of the Berlin Reichswehr, for support. Lüttwitz, an organiser of Freikorps units in 1918–19 and a fervent monarchist, responded by calling on President Friedrich Ebert and Defense Minister Gustav Noske to stop the whole programme of troop reductions. When Ebert refused, Lüttwitz ordered the Marinebrigade Ehrhardt to march on Berlin. It occupied the capital on March 13, 1920. Lüttwitz, therefore, was the driving force behind the 1920 putsch. Its nominal leader, though, was Wolfgang Kapp, a 62-year-old East Prussian civil servant and fervent nationalist.
At this point Noske called upon the regular army to suppress the putsch. He encountered a blank refusal. The Chef der Heeresleitung General Hans von Seeckt, one of the Reichswehr's senior commanders, told him: "Reichswehr does not shoot on Reichswehr". The government, forced to abandon Berlin, moved to Stuttgart. As it did so it issued a proclamation calling on Germany's workers to defeat the putsch by means of a general strike. The strike call received massive support. With the country paralysed, the putsch collapsed, and Kapp and Lüttwitz, unable to govern, fled to Sweden.