First and Second Expeditions

After serving under the leadership of Joseph N. Nicollet, Frémont was given his first chance to lead his own expedition. Frémont’s skills as a surveyor, mathematician, explorer, and leader would be tested as he explored deeper into the American West. Frémont’s first two expeditions as leader were his most famous. It was these expeditions that earned him the nickname the “Pathfinder” and made him a national celebrity. The official report of these first two expeditions gives us an interesting peak into the life of a western explorer.

Becoming the Pathfinder

 Platte River Passage. Memoir of the life and public services of John Charles Frémont. Georia Historical Society Main Collection.

Platte River Passage. Memoir of the Life and Public Services of John Charles Frémont. Georgia Historical Society Main Collection.

In the spring of 1842, John Charles was given orders from the Corps of Topographical Engineers to survey and map the emigrant route to Oregon known as the Oregon Trail. The exploring party left from Missouri and traveled northwest through the modern states of Nebraska, Colorado, and Wyoming.

In 1844, Frémont received orders to lead another expedition to find a more southern route across the Rockies and explore the area south of the Columbia River. Frémont would complete his official orders and more, crossing into the Mexican province of California.

The official reports from his first two expeditions were combined and published in 1845 as Report of the Exploring Expedition to the Rocky Mountains in the Year 1842: And to Oregon and North California in the Years 1843-44. The Report was very popular. Thousands of copies of the Report were printed by Congress and soon private publishers were selling editions with added illustrations and commentary. Frémont became a national celebrity and was given the nickname the “Pathfinder.”


Map of Explorations Created by Daniel Watkins.

Think About It

Brigham Young, 1801-1877, half-length portrait, facing left, 1854. Library of Congress Prints & Photographs Division, LC-USZ62-50426.

Brigham Young, 1801-1877, half-length portrait, facing left, 1854. Library of Congress Prints & Photographs Division, LC-USZ62-50426.

One American influenced by the 1843 and 1845 reports was Brigham Young, an influential leader of the Mormon community. By the 1840s, the Mormons (members of the Church of Jesus Christ of Latter-day Saints) had already moved as far as Iowa and Illinois but conflict with non-Mormons in the area led to their settlement in the Salt Lake Region of the Great Basin (modern-day Utah). Joseph Smith and other Mormon leaders had discussed the possibility of relocating to the Rocky Mountain region before Frémont’s reports were published, but Frémont’s detailed maps and glowing descriptions of the region along with other reports from explorers and fur traders helped Young make his final decision.

From the Source

Would you ever take a trip without a map, GPS, or directions to your final location? Would you consider moving somewhere if there was no official map of the route you would take?

Emigrants traveling to Oregon Country (the area including present-day Oregon, Washington, and Idaho) before Frémont published his report in 1843 did so without an official map. Frémont’s first and second expeditions journeyed into territory unfamiliar to most Americans. Frémont’s descriptions of the land, wildlife, Native Americans, and scenery shaped the nations’ view of the West and contributed to the increased enthusiasm for expanding and settling the western frontier of the United States.

In 1845, newspaper editor John Sullivan coined the term “manifest destiny” to describe the growing belief that the United States was called by a higher power to expand from coast to coast. Emigrants heading out west on the Oregon Trail used Frémont’s Report as both a practical guidebook along the trail and a source of inspiration on their journey to start a new life in the Oregon Territories.

Read the selected pages from the 1845 Report detailing the exploration of the Great Salt Lake in present-day Utah. Click on the thumbnail to download the report.

Great Salt Lake_BW

Click on the thumbnail to download a PDF excerpt from the report.

  • What mineral makes the Great Salt Lake so famous? Why did the party only collect a small amount of the salt?
  • What purpose does Frémont give for sketching the map of the Great Salt Lake region?
  • Why did the exploring party end its exploration of the Great Salt Lake when it did?
  • What did Frémont accidently leave on the summit where they were making observations?
  • Did Frémont describe the Great Salt Lake in a positive or negative way?
  • Do you think this description of the Great Salt Lake region might encourage emigrants to the area?




Map Analysis

Map of an exploring expedition to the Rocky Mountains in the year 1842 and to Oregon & north California in the years 1843-44.

The maps included in the Report might be the most important geographic and scientific contribution of the expeditions. Charles Preuss joined both the 1842 and 1843-44 expeditions as chief cartographer and artist. Preuss actually drew the maps and illustrations for both reports. The main map in the 1845 Report corrected wrong ideas about the geography of the West, added new understandings about the region, and provided a practical map for emigrant travel. The map also was the first to name and describe the Great Basin.


Math of Exploration Challenge

To be a good explorer in the nineteenth century, you had to be good at math. It was only through math and science that you could find your way through uncharted territories. As a young man, Frémont became fascinated with astronomical calculations after reading a book from his College’s library. The book, written in Dutch, contained maps and charts of the stars and the calculations used to figure longitude and latitude from observations of the night’s sky.

Frémont was not always gifted at math; in his Memoirs, Frémont admits that he entered the College of Charleston behind in mathematics. With study and practice, he developed the mathematical skills needed to lead the members of his exploring team on adventures through the American West.

Do you have the math skills needed for adventure? Test your math abilities with these questions using data from the Report.

Click on the thumbnails to see a larger version of each page, or click here to download a PDF with all four pages.

Use the Table of Distances from the 1845 Report to answer the following questions.

  • Between May 29, 1843, and August 1, 1844, on what single day did the expedition members travel the longest distance?
  • Did the expedition travel more miles in July 1843 or July 1844?
  • Give the mean, median, and mode of distance traveled by the expedition in October 1843. Assume that the members of the expedition traveled 0 miles on October 23rd and 27th.
  • Assuming the members of the expedition traveled at a steady pace for 6 hours on November 28, 1843, estimate how many miles per hour they were traveling.
  • May 4, 1844 – 57 miles
  • July 1844
  • 17.74, 20, 26
  • 3.5mph

Tools of the Trade

Below is a list of instruments taken by John C. Frémont on his Second Expedition.
Fremont list of instruments 2nd expedition

See if you can match the description of each instrument to the correct image.

1.Tools of the Trade Match-up 01 2.Tools of the Trade Match-up 02 3.Tools of the Trade Match-up 03

4.Tools of the Trade Match-up 045.Tools of the Trade Match-up 05

6.Tools of the Trade Match-up 06 7.Tools of the Trade Match-up 07


A. Reflecting Circle: complete circular instrument graduated to 720°. An astronomical instrument for measuring angles, like the sextant or Hadley’s quadrant.

B. Compass: navigational instrument for finding directions.

C. Sextant: device that measures the angle between two objects. The scale of a sextant has a length of ⅙ of a turn (60°).

D. Refracting Telescope: type of optical telescope that uses a lens as its objective to form an image. The refracting telescope design was originally used in spy glasses and astronomical telescopes but is also used for long focus camera lenses.

E. Chronometer: chronometer small enough to fit in your pocket. A chronometer is a watch designed to keep very accurate time. Chronometers are used by explorers to calculate longitude.

F. Cistern Barometer: barometer with a straight glass tube, closed at the top end and with the bottom end dipped in a small chamber, or cistern, containing the mercury.

G. Syphon Barometer: barometer with a tube bent like a hook with the longer leg closed at the top. The height of the mercury in the longer leg shows the pressure of the atmosphere.

1. F 2. G 3. C 4. E 5. D 6. A 7. B

Continue to Third, Fourth, and Fifth Expeditions