Lahr was a male Gelfling who lived around 800 trine after The Great Division. Originally a peaceful Mounder shepherd accompanied by a Fizzgig-like animal called Whouf, Lahr's village was destroyed by the Garthim, sent by the Skeksis to thwart the prophecy that a Gefling would find the shard and heal the Dark Crystal. After discovering the ruins of his home, Lahr was attacked by a Garthim, and managed to kill it by stabbing it with his flute, becoming the first of his kind to best a Garthim in combat.
Whilst looking for survivors, he encountered Neffi, a survivor of the village of Greengrove. The two arrived at the Namopo Valley, where other survivors had taken refuge. Lahr advocated fighting back against the Garthim rather than retreating, revealing his own encounter with the Garthim. His stance was embraced when the Garthim began to converge on the Valley. Creating weapons out of everyday objects, the Gelflings managed to drive off the attack, but several were taken as prisoners.