Mauhur was a captain of the Orcs, leader of a band of fighting Uruk-hai who came as reinforcements to the company of Ugluk that was bearing the captive hobbits Merry and Pippin across Rohan. He fell upon the rear of the Riders of Rohan who had ringed the orcs near the eaves of Fangorn; but the onslaught failed, and in the confusion of that night battle the two hobbits slipped away into the forest.