The story
From the verse Deutschland, Deutschland über alles, über alles in der Welt (“Germany, Germany above all, above all in the world”), from the German national anthem Lied der Deutschen, composed by Joseph Haydn in 1797. The verse originally meant that the Germans and their rulers have to overcome existing divisions and keep in mind the goal of a unified Germany.
Etymology from Wiktionary, CC BY-SA 4.0.