Lewis and Clark's Expedition from Missouri to the Pacific

The Lewis and Clark expedition was an important journey and one of the most important historical events in the history of the United States. This event was actually a real estate deal in which President Thomas Jefferson arranged for the purchase of the Louisiana territory in 1803. This purchase from the French is called the Louisiana Purchase. It was significant because by buying this territory the United State was able to increase in size and new areas were now open for expansion. Shortly following the Louisiana Purchase, Jefferson sent Meriwether Lewis and William Clark on the first exploration of the new territory. This was called the Corps of Discovery, or the Lewis and Clark Expedition.

One of the reasons why President Jefferson called on the Corps of Discovery was to find a northwest passage. This passage would be a route of connecting rivers that would go through the Rocky Mountains and link the Columbia and Missouri Rivers. He also wanted to establish his authority over the Indians and to discover as much as possible about the new lands. To command the expedition, Meriwether Lewis was chosen by President Jefferson. His experience included being a former Captain in the U.S. Army, a skilled frontiersmen, and he was the secretary to the President. Lewis recruited William Clark to help him unofficially command the Corps of Discovery. Clark, like Lewis, had once been a part of the Army. He was also a very skilled frontiersman and draftsman. In addition to Lewis and Clark, there were thirty-three other members. Some of these members were military and others were not. For example, a non-military member of the party was a man named York who was a slave of William Clark.

The journey began outside of Missouri in 1804. Their journey that year lasted from the summer to the fall. They traveled upstream until they reached Fort Mandan where they would wait over the winter and get ready for the second half of their journey. In 1805, during the spring, The Expedition began its travels through Missouri to what is now Three Forks, Montana. They met the Shoshone Indians who helped them over the Bitterroot Mountains by providing them with horses. After crossing the mountains the members of the expedition needed to travel to what is now Oregon. To do this they made canoes that they used to travel down the Columbia river. This is where they stayed until the winter passed and they returned home. Through their travels they had a number of encounters. These encounters allowed them to meet various groups of Native Americans with whom they set-up diplomatic relationships. They carefully recorded their journey and findings by taking notes and by making drawings of the many creatures and items that they came across. William Clark drew detailed maps of rivers and other waterways.

By the time the journey ended in 1806 much of Jefferson's wishes for the expedition were met. The maps of water routes would be used by future explorers, both American and immigrant, to go further into the western part of the country. This would continue for two centuries and would play a part in eventually pushing Native Americans into reservations, and changing the landscape from one of nature to one of cities and farms. It would also end in the displacement of animal life, such as the wild buffalo.

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  • National Geographic – Go West Across America with Lewis and Clark: National Geographic provides information to readers about the trek westward and about Lewis and Clark themselves.
  • Lewis and Clark - The Journey of the Corps of Discovery: PBS provides readers with in-depth information about the Lewis and Clark expedition. Visitors will be able to learn more about the Corps, the Native Americans that they encountered, view an interactive trail and interactive story, and find further resources for the classroom.
  • Lewis and Clark - Corps of Discovery: This is the home page for the United States Army web page about Lewis and Clark. Visitors to this site can click on further information to learn about the mission and about the people.
  • Lewis and Clark Bicentennial Exhibit: This page for the Lewis and Clark exhibition. It includes an online exhibit that opens and plays in a new window.
  • Lewis and Clark Expedition: This is a guide that appears on the National Park Service. It includes an interactive guide of the Lewis and Clark Expedition.
  • Grizzly Survival: Visitors will learn here about Lewis and Clark's encounters with grizzly bears.
  • Lewis and Clark Expedition: When viewing this page readers can click on the side links for further information about Lewis and Clark and their journey. Links include biographies, plants, the expedition, and Native Americans.
  • U.S. Fish & Wildlife Service: Lewis & Clark Expedition - Scientific Discovery: Here people will learn about the scientific discoveries made by Lewis and Clark. Readers can also learn more about the mission, and the landscapes they encountered.
  • University of Nebraska-Lincoln: Journals of the Lewis and Clark Expedition Online: An archive of the full text of Lewis and Clark's journals of their journey to the west. This includes nearly 5,000 pages of texts, all of which is searchable and easy to navigate.
  • University of Colorado: Lewis and Clark Expedition: A short overview of the history of the Lewis and Clark Expedition. Includes information about the background of the mission, the preparations taken, encounters with the Spanish and Native Americans, and the trip back home.
  • Lewis and Clark Meet the Shoshone: This appears on the America Story from America's Library. Readers will learn how Lewis and Clark met with the Shoshone Indians and how they were helped by them.
  • American Treasures of the Library of Congress: The Lewis and Clark Expedition: On this page viewers can read a brief overview of the Lewis and Clark Expedition. Readers can also find images of maps here.
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