In the summer of 1885 Liszt conceived the idea of setting music to a picture by Wilhelm von Kaulbach (1855-1874), one of the set of six frescos on a wall of the Raczynski Gallery in the New Museum at Berlin. The subject of this picture "The Battle of the Huns" (Hunnenschlacht), is the legend which tells of the terrific aërial battle between the ghosts of the slain Huns and Romans after the struggle outside the walls of Rome, in 451, which engaged the forces of Attila and of Theodoric the Visigoth. The picture has been thus described: "According to a legend, the combatants were so exasperated that the slain rose during the night and fought in the air. Rome, which is seen in the background, is said to have been the scene of this event. Above, borne on a shield, is Attila with a scourge in his hand; opposite him Theodoric, king of the Visigoths. The foreground is a battle-field, strewn with corpses, which are seen to be gradually reviving, rising up, and rallying, while among them wander wailing and lamenting women."
Liszt's symphonic poem (completed early in 1857) has been found by commentators to typify the conflict between Heathendom and Christianity, eventuating in the triumph of the Cross. The comment of Liszt himself, contained in a letter written in May, 1857, to the wife of Kaulbach, is, naturally, as authoritative as it is valuable: "I have been encouraged," he says, "to send you what indeed truly belongs to you, but what, alas! I must send in so shabby a dress that I must beg from you all the indulgence that you have so often kindly shown me. At the same time with these lines you will receive the manuscript of the two-pianoforte arrangement of my symphonic poem, 'The Battle of the Huns' (written for a large orchestra and completed by the end of last February), and I beg you, dear madam, to do me the favor to accept this work as a token of my great reverence and most devoted friendship towards the master of masters. Perhaps there may be an opportunity later on, in Munich or Weimar, in which I can have the work performed before you with full orchestra, and can give a voice to the meteoric and solar light which I have borrowed from the painting, and which at the Finale I have formed into one whole by the gradual working up of the Catholic choral 'Crux fidelis' and the meteoric sparks blended therewith. As I have already intimated to Kaulbach in Munich, I was led by the musical demands of the material to give proportionately more place to the solar light of Christianity, personified in the Catholic choral 'Crux fidelis,' than appears to be the case in the glorious painting, in order thereby to win and pregnantly represent the conclusion of the Victory of the Cross, with which I, both as a Catholic and as a man, could not dispense."[79]