American History 1785 - 1849

United States History The Louisiana Purchase

William Clark

Meriwether Lewis 
William Clark 

Meriwether Lewis

President Thomas Jefferson sent two young army officers, Meriwether Lewis and William Clark, to find out all they could about the new land. They were to:

  • look for the beginnings of the Missouri River
  •  find a way through the Rocky Mountains to the Pacific Ocean
  • learn about the Indians
  • find out about plants, animals, minerals (coal, oil, gas, gold, silver, etc.)
  • make maps

Lewis and Clark took 27 other men with them. They started their journey in St. Louis in May of 1804. The traveled 1,600 miles up the Missouri until they reached what is now South Dakota. There they found an Indian girl named Sacagawea. They hired her and her husband to guide them through the Rocky Mountains.

On the journey they traveled by wagon, canoe, and by foot. They crossed the mountains and found the Columbia River. They followed the Columbia River to the Pacific Ocean. Lewis and Clark took a different route back home. They returned in 1806. During the trip only one man died from an illness. Descriptions and reports were written up in newspapers for everyone to read.

Lewis and Clark Expedition Map

Map Credit



One day while Sacagawea and her brother were hunting, the Minnetaree Indians attacked their Shoshone village. They killed Sacagawea's father and captured Sacagawea. Sacagawea went from being a princess to being a slave. When Sacagawea became too old to be a Minnetaree slave, she was sold to Charbonneau. Charbonneau was a trapper from Canada. He married Sacagawea and took her to the Mandan village. The Mandans lived much the same as the Minnetaree.

One day some white men, guided by Lewis and Clark, arrived in the Mandan village. Charbonneau said he would travel west with Lewis and Clark when the spring came. They needed a guide. In February Sacagawea and Charbonneau had a baby and named him Pomp. Captain Clark wanted Sacagawea to travel with the group because she spoke the Shoshone language and could ask the Shoshone Indians for horses to travel west. Sacagawea was the only one who could speak the Shoshone language. Sacagawea represented peace as she traveled with Lewis and Clark because war parties did not travel with women and children.

They had many adventures on the journey. When Lewis and Clark came to a waterfall they built wagons to carry the boats across the land. While traveling over land up a steep, rocky hill the rain poured and filled up the canyon. Sacagawea slipped. Captain Clark helped her and Pomp climb out. The travelers also ran into rattlesnakes and grizzly bears.

After coming to a three branch split in the river, the group had to guess which branch to take. Captain Lewis named the river they were traveling on for his friend Thomas Jefferson.


Sacagawea knew she had reached her home when she found the rocks she had hidden behind during the Minnetaree raid. The explorers found old campfires and footprints but no Indians. Sacagawea was sad when she walked through Indian village because she could not find her family. When Sacagawea reached the chief's teepee, she found her brother. She told her brother how Clark had saved her life and that he was her friend. Then she asked for horses for their trip west.

Sacagawea had to decide if she would go on with Lewis and Clark or stay with the Shoshone. She decided to go. Lewis and Clark traveled by horseback over the Rocky Mountains. The group then traveled on the rivers for three months.

After reaching the Pacific Ocean the men built a fort to live in during the winter. Sacagawea felt happy for helping Lewis and Clark find the Pacific Ocean and for also finding her people. In the spring, Sacagawea returned to the Shoshone Indian village. When she returned, Sacagawea could not find her brother. No one knows if she ever saw him again.



Zebulon Pike

Zebulon Pike

In 1805 another officer, Zebulon Pike, was sent to explore the Mississippi River. On his second trip he traveled across the plains to the Rocky Mountains and into the Southwest. Pike traveled to Santa Fe in New Mexico. He opened up trade between the Spanish settlers and the Americans in the East. Pike found a high peak that was 14,110 feet tall. It was named after him - Pike's Peak.

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