American explorer and Governor (1774–1809)
Source (Wikipedia): Meriwether Lewis

Meriwether Lewis was an American explorer, soldier, politician, and public administrator, best known for his role as the leader of the Lewis and Clark Expedition, also known as the Corps of Discovery, with William Clark. Their mission was to explore the territory of the Louisiana Purchase, establish trade with, and sovereignty over the natives near the Missouri River, and claim the Pacific Northwest and Oregon Country for the United States before European nations. They also collected scientific data and information on indigenous nations. President Thomas Jefferson appointed him Governor of Upper Louisiana in 1806. He died in 1809 of gunshot wounds, in what was either a murder or suicide.