Adolf Hitler's bodyguard
When Hitler returned to Munich from military service in 1918, he became a member of the Nazi Party, an extremist far-right political party in Bavaria. In 1921, he was elected leader of the party. As his speeches promoted violence and racism, Hitler needed permanent security.
Führerprinzip
In the case of the Nazis, the "Führerprinzip" became integral to the Nazi Party in July 1921, when Adolf Hitler forced a showdown with the original leaders of the party after he learned that they were attempting to merge it with the somewhat larger German Socialist Party. Learning of this, and knowing that any merger would dilute his influence over the group, Hitler quit the Nazis. Realizing that the party would be completely ineffective without Hitler as their front man, the founder of the party, Anton Drexler, opened negotiations with Hitler, who delivered an ultimatum: he must be recognized as the sole leader ("Führer") of the party, with dictatorial powers. The executive committee gave in to his demands, and Hitler rejoined the party a few days later to become its permanent ruler, with Drexler kicked upstairs to be honorary chairman for life.