Núrzum is dead, but the enemy still roams free throughout much of Wildermore.
'Hail, ${PLAYER}! Your valour drove back Núrzum, but the forces of Isengard do not seem to care that their leader has fallen. They continue to swarm our lands in great numbers.
'The enemy is especially strong in the Whitshaws today. Go there, and show them that Wildermore will endure!'
The forces of Isengard can be found in the Whitshaws.
You should ride to the Whitshaws and defeat the enemies of Wildermore.