After his return from Rome, Arminius became a trusted advisor to Varus,[30] but in secret he forged an alliance of Germanic tribes that had traditionally been enemies. These included the Cherusci,[13] Marsi,[13] Chatti,[13] Bructeri,[13] Chauci, Sicambri, and remaining elements of the Suebi, who had been defeated by Caesar in the Battle of Vosges. These five were some of the fifty Germanic tribes at the time.[31] Using the collective outrage over Varus' tyrannous insolence and wanton cruelty to the conquered,[23] Arminius was able to unite the disorganized tribes who had submitted in sullen hatred to the Roman dominion, and maintain said alliance until the most opportune moment to strike

While Varus was on his way from his summer camp west of the Weser river to winter headquarters near the Rhine, he heard reports of a local rebellion, reports which had been fabricated by Arminius.[14] Edward Shepherd Creasy writes that "This was represented to Varus as an occasion which required his prompt attendance at the spot; but he was kept in studied ignorance of its being part of a concerted national rising; and he still looked on Arminius as his submissive vassal ...".

Varus decided to quell this uprising immediately, expediting his response by taking a detour through territory that was unfamiliar to the Romans. Arminius, who accompanied him, directed him along a route that would facilitate an ambush.[14] Another Cheruscan nobleman, Segestes, brother of Segimerus and unwilling father-in-law to Arminius,[27][33] warned Varus the night before the Roman forces departed, allegedly suggesting that Varus should apprehend Arminius, along with other Germanic leaders whom he identified as participants in the planned uprising. His warning, however, was dismissed as stemming from the personal feud between Segestes and Arminius. Arminius then left under the pretext of drumming up Germanic forces to support the Roman campaign. Once free from prying eyes, he immediately led his troops in a series of attacks on the surrounding Roman garrisons.

Despite several successful campaigns and raids by the Romans in the years after the battle, they never again attempted to conquer the Germanic territories east of the Rhine river. The victory of the Germanic tribes against Rome's legions in the Teutoburg Forest would have far-reaching effects on the subsequent history of both the ancient Germanic peoples and the Roman Empire. Contemporary and modern historians have generally regarded Arminius' victory over Varus as "Rome's greatest defeat",[4] one of the most decisive battles recorded in military history,[5][6][7][8][9] and as "a turning-point in world history".[10]

(http://www.autoadmit.com/thread.php?thread_id=4155280&forum_id=2#37402118)