5. Panzerarmee

The paratroopers of the 101st Airborne Division were brought to Bastogne on December 17, 1944 to stop the advancement of the German forces and to defend the main roads to town. The 5. Panzerarmee (5th Armored Army) passed Bastogne north and south without losing time with capturing this well defended city. So the 101st ended up surrounded.
The Germans were stopped at Dinant and couldn’t cross the river Maas. They couldn’t go on, so Oberbefehlshaber Von Manteuffel decided to go back and capture Bastogne first. The Germans demanded the American troops to give up, but general Anthony McAuliffe answered, "Nuts!"