First of all, it was Meriwhether Lewis who was assigned to explore the West. Clark would offer to join up with the Discovery Corp weeks after Meriwether Lewis started his journey. And it was President Thomas Jefferson who assigned Lewis.
They did not "move" West. President Thomas Jefferson assigned Lewis and his team to explore the newly purchased Louisiana Territory and Clark would join him soon after.
President Jefferson needed Lewis and Clark to map the Louisiana Territory and to explore it.
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The Lewis and Clark Expedition : Captain Meriwether Lewis and Second Lieutenant William Clark .
1803
Thomas Jefferson was president at the time of the Lewis and Clark Expedition. infact, he sent Lewis out to explore and Lewis chose Clark to come along. So, Thomas Jefferson had a huge influence on the expedition.
Thomas Jefferson gave Lewis and Clark $2,500.
Thomas Jefferson hired Lewis & Clark to explore the west.
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