La Marseillaise as performed by an actual French person [Mireille Mathieu]:
Gratuitous high school French class flashback:
Allons enfants de la Patrie
Le jour de gloire est arrivé !
Contre nous de la tyrannie
L'étendard sanglant est levé
Entendez-vous dans nos campagnes
Mugir ces féroces soldats?
Ils viennent jusque dans vos bras.
Égorger vos fils, vos compagnes!
Aux armes citoyens!
Formez vos bataillons!
Qu'un sang impur
Abreuve nos sillons!
From Wikipedia [where you can find the hair-raising lyrics in English]:
"La Marseillaise" is a song written and composed by Claude Joseph Rouget de Lisle in Strasbourg on April 25, 1792... It became the rallying call of the French Revolution and received its name because it was first sung on the streets by volunteers (fédérés) from Marseille upon their arrival in Paris after a young volunteer from Montpellier called François Mireur had sung it at a patriotic gathering in Marseilles. A freshly graduated medical doctor, Mireur later became a general with Bonaparte and died in Egypt at 28.A few summers ago I was having breakfast with a bunch of people at a friend's ranch and a fellow guest [she breeds and trains Rottweilers] said, "It's Bastille Day!" And all of us at the table started to sing the Marseillaise and someone asked, "How do you know that?" and we all answered at the same time, "Everybody knows it [kind of]!" Aux armes, citoyens...! [marches off to kitchen, followed by the pack]
Its lyrics are heavily oriented toward Prussian and Austrian armies which were attacking France at the time (Strasbourg itself was attacked just a few days after). The Battle of Valmy turned the tables.