* Native American History: The Klamath, Modoc, and other Native American tribes have lived in the area for thousands of years and considered Mount Shasta sacred. They were undoubtedly the first to know and interact with the mountain.

* European Exploration: The first documented European sighting of Mount Shasta likely occurred in the 18th century by Spanish explorers. However, it's difficult to pinpoint an individual as the "discoverer" because these explorers were often traveling as part of larger expeditions.

* Early Settlers: As European settlers began arriving in the 19th century, the mountain became more widely known. Early settlers used it as a landmark and a source of timber.

Therefore, it's more accurate to say that Mount Shasta was "discovered" by multiple groups over time, rather than a single individual. The mountain has always held significance for those who have lived around it, from the Native American tribes to early explorers and settlers.