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NGA in History - Defining Moments

Corps of Discovery

The United States geospatial intelligence effort began in earnest in 1803 with President Thomas Jefferson. In a classified tasking, Jefferson sent Meriwether Lewis, William Clark and their Corps of Discovery to explore the newly acquired Louisiana Purchase and other lands west of the Mississippi River. They were to report on European and Indian military forces and alliances, trade patterns, and the geography, plant life and animals they found.

Planned and funded secretly, this was the first large government effort to explore the new lands Jefferson had purchased from France. With open and classified missions, Lewis and Clark created products that included new maps of the territory reflecting their adventures. As the nation looked west, other military and civilian expeditions followed Lewis and Clark and expanded our knowledge of the Earth. Many other expeditions followed, driven not only by the desire for scientific discovery, but also by the need to show the way for America’s increasing migrations westward.

The National Geospatial-Intelligence Agency proudly following in the footsteps of explorers like Lewis and Clark. Our motto, “Know the Earth… Show the Way… Understand the World,” reflect not only our own mission, but the mission of the Corps of Discovery two centuries ago.

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