Nazi Party
"Deutsche Gemeinschaft" was a branch of the Nazi Party founded in 1919, created for Germans with "Volksdeutsche" status. It is not to be confused with the post-war right-wing "", which was founded in 1949.
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.