John Frémont initiates a second expedition that…

John Frémont initiates a second expedition that circumscribes the least known portions of the American West, traveling from the Colorado Rocky Mountains north to the South Pass, northwest to the Columbia River, south along the Cascade and Sierra Nevada ranges into California and southward, where he winters at the turn of 1843.

Frémont's successful first expedition had led quickly to a second; it begins in the summer of 1843.

The more ambitious goal this time is to map and describe the second half of the Oregon Trail, find an alternate route to the South Pass, and push westward toward the Pacific Ocean on the Columbia River in Oregon Country.

Frémont and his almost forty well-equipped men, had left the Missouri River in May, after he controversially obtained a twelve-pound howitzer cannon in St. Louis.

Frémont had invited Kit Carson on the second expedition, due to his proven skills, and he had joined Frémont's party on the Arkansas River.

Unable to find a new route through Colorado to the South Pass, Frémont takes to the regular Oregon Trail, passing the main body of the great immigration of 1843.

His party stops to explore the northern part of the Great Salt Lake, then travels by way Fort Hall and Fort Boise to Marcus Whitman's mission, along the Snake River to the Columbia River and in to Oregon.

Frémont's endurance, energy, and resourcefulness over the long journey are remarkable.

Traveling west along the Columbia, they have come within sight of the Cascade Range peaks and mapped Mount St. Helens and Mount Hood.

Reaching the Dalles on November 5, Frémont leaves his party and travels to British Fort Vancouver for supplies.