Sources include Antapodosis, seu rerum per Europam gestarum, written by Liutprand of Cremona,[3] Continuator Reginonis, Annales Alamannici,[4] and the necrologies of the Swabian counts Gozbert and Managolt, who were killed in this battle.

The chronicle Annalium Boiorum VII, written in the 16th century by the Bavarian humanist Johannes Aventinus, gives a detailed narration of the battle, relying on older documents which today are lost.

In 908 a Hungarian army invaded Thuringia and were victorious at Eisenach, killing the co-dukes Burchard and Egino, as well as Rudolf I, Bishop of Würzburg.

Possibly desirous of repeating the victorious campaigns of his ancestor Charles the Great against the Avars which ended with the subjugation of the latter (though unmindful of the fate of Luitpold in the Battle of Pressburg three years earlier), King Louis decided that forces from all the German duchies should come together to fight the Hungarians.

[10] The king and his troops arrived near the city of Augsburg, on the plains of Gunzenle, near the Lech river, and waited for the Frankish army led by Gebhard, Duke of Lorraine to appear and join them against the Hungarians.

From the work of Aventinus: Annalium Boiorum volume VII, we can reconstruct their route: After they had crossed Bavaria via the River Enns, they reached Augsburg through Tegernsee, then Sandau near to Landsberg am Lech.

This shows that Hungarian intelligence worked very effectively not only within Hungary, but also in enemy territory, making possible the rapid movement of military operations onto the opponent's land.

But still, in order to lure the German soldiers after them, the Hungarians had to move very close, and even start short hand-to-hand skirmishes with the superior Germans, in the places of the defensive line, where they saw weaknesses, then to run, when the situation started to be severe, convincing the enemy that he is about to win, persuading him to pursue them, and with this to break his battle formation, giving them the opportunity to exploit this, and inflict heavy losses on them.

[26] Nevertheless, this shows that the Hungarians used again psychological warfare tactics, making the enemy troops to be frightened, or to lose their will to fight, or to be exaggeratedly self-conceited, which made them easier to defeat.

The Hungarians also used psychological warfare in another battle that occurred 11 years earlier: the Battle of Brenta River, feigning defeat in an early skirmish, then running away, showing to the enemy commanders that they had despaired, then sending envoys to them asking for forgiveness, with this convincing the enemy to feel pretentious and comfortable, then striking in an unexpected moment and destroying the Italian army.

[27] During the whole battle of Augsburg, the Hungarians waited for this moment, hiding their reserve troops in woods[28] that allowed huge numbers of soldiers to be concealed.

[29] In this moment, the retreating Hungarian main troops turned back and attacked the Germans from the front, resisting their charge, and not letting them break their line.

[30] At that moment those Hungarian units who came from the rear and sides of the Swabians surrounded them completely, and entered into a final hand-to-hand fight with the hopeless enemy.

[31] This shows that before the battle, the Hungarian commander chose carefully a place near the initial battlefield, with two woods near to each other, in which he could hide some of his troops, which waited until the pursuing Germans passed them, and then attacked them.

This shows the great patience of the Hungarian commander, who in the whole day conducted manoeuvres which diverted the enemy's attention from his real purpose.

When the king's people, who did not think of a trick, began to pursue them with great vigor, the ambushers, whom they believed to be defeated, attacked them from all sides and killed the Christians who thought they were victorious.

After these two battles the Hungarian army plundered and burned the German territories while nobody tried to fight them off again, retreating to the walled towns and castles, and waiting for them to turn back to Hungary.

This is demonstrated by the fact that after these defeats, Louis IV the Child, the German king, together with the Swabian, Frankish, Bavarian and Saxonian princes, agreed to pay tribute to the Hungarians.