Following the defeat of the German Empire, Ehrhardt formed the II.Marine Brigade. A strong opponent of the Treaty of Versailles, he held strong monarchist views. The II.Marine Brigade was a force of around 6,000 men. They fought in north-west Germany, central Germany, Upper Silesia, and Bavaria and participated in the unsuccessful Kapp-Lüttwitz Putsch of 1920. After the failed Putsch, Ehrhardt fled Germany, returning at a later time. In Bavaria, which was ruled by Gustav von Kahr at that time, he formed the Organisation Consul, and later the Viking League ("Bund Wiking"), a secret military society.