Die Fahne Hoch, usually called Horst Wessel Lied ("The Horst Wessel Song") was the marching song of Adolf Hitler's Sturmabteilung, the SA or "Stormtroopers." It also became the anthem of the Nazi party and thus the unofficial national anthem of Germany when the Nazis seized power in 1933.

"The Horst Wessel Song" is so called because it was originally a poem by the ill-fated Horst Wessel, which was set to music after his death. Much like "The Star-Spangled Banner" it is not an original tune, but rather an old folk melody, from which the hymn "How Great Thou Art" is probably also descended.

Horst Wessel Lied

Die Fahne hoch! Die Reihen fest geschlossen!
S.A. marschiert mit ruhig festem Schritt.
Kameraden, die Rotfront und Reaction erschossen,
marschiern im geist in unserm Reihen mit.

Die Strasse frei den braunen Bataillonen!
Die Strasse frei dem Sturmabteilungsmann!
Es schaun aufs hakenkreuz voll hoffnung schon Millionen.
Der Tag für Freiheit und fuer Brot bricht an.

Zum letztenmal wird nun Appell geblasen!
Zum kampf stehn wir alle schon bereit.
Bald flattern hitlerfahnen ueber allen Strassen,
die knechtschaft dauert nur noch kurze Zeit!

Die Fahne hoch! Die Reihen fest geschlossen!
S.A. marschiert mit ruhig festem Schritt.
Kameraden, die Rotfront und Reaction erschossen,
marschiern im geist in unserm Reihen mit.

Or, in English:

The Horst Wessel Song

Hold high the banner! Close the hard ranks serried!
SA marches on with sturdy stride.
Comrades, by Red Front and Reaction killed, are buried,
But march with us in image at our side.

Gangway! Gangway! Now for the Brown battalions!
For Storm Troopers clear road o'er land!
The Swastika gives hope to our entranced millions,
The day for freedom and for bread's at hand.

The trumpet blows its shrill and final blast!
Prepared for war and battle here we stand.
Soon Hitler's banners will wave unchecked at last,
The end of German slav'ry in our land.

Hold high the banner! Close the hard ranks serried!
SA marches on with sturdy stride.
Comrades, by Red Front and Reaction killed, are buried,
But march with us in image at our side.


A little modern "Horst Wessel Song" trivia: you can hear the scratchy anthem playing on radios scattered throughout the single-player levels of the first-person shooter Return to Castle Wolfenstein.

You can hear a small excerpt of "The Horst Wessel Song," sung by SA soldiers with band accompaniment, at http://cidc.library.cornell.edu/dof/germany/sounds/Horst.aif - it's oddly creepy.

Sources:
Anesi, Chuck, "The Escape Route of Martin Bormann." http://www.anesi.com/east/bormann.htm
Broderick, George, "Die Fahne Hoch! History and Development of the Horst-Wessel-Lied," http://www.smo.uhi.ac.uk/~kelly/LIST/ARTICLE/Broderick/DIE%20FAHNE%20HOCH!.html The Calvin German Propaganda Archive, http://www.calvin.edu/academic/cas/gpa/
Translation by Snyder, Louis, from Encyclopedia of the Third Reich, Marlowe & Co., 1997. This isn't an exact translation, but the direct translations I found are clunky and I'm not sufficiently capable to produce my own.