Discovering Our Past: The American Journey to World War I

Chapter 11: Manifest Destiny

Chapter Overview

In the first half of the nineteenth century Americans spread westward across the continent. Living by trapping beaver and trading furs, mountain men explored the mountains, valleys, and trails of the West. In Oregon, missionaries were followed by thousands of pioneers searching for rich farmland, a new life, and adventure. The first large-scale wagon train left Independence, Missouri, for Oregon in 1843. As the number of American settlers in the Oregon Country increased, the United States and Great Britain clashed over the northern border of Oregon. In 1846, the two countries compromised by setting the boundary at 49°N.

In Texas land was offered to people who were willing to bring their families to settle there. By 1830 Americans in Texas far outnumbered Mexicans. The Mexican government became alarmed and began limiting U.S. immigration to and trade with Texas, leading some American settlers to call for independence. At the Battle of the Alamo, a small Texas force held off several thousand Mexican troops for 13 days. Although all of the defenders were eventually defeated and killed, their courage inspired others in the fight for freedom. At the Battle of San Jacinto, the Texans surprised the Mexican army and won independence for Texas. In 1845, Texas became part of the United States.

The United States and Mexico did not agree on the southern border of Texas. In addition, the United States wanted to buy New Mexico and California. Many Americans, including President James K. Polk, believed in Manifest Destiny—the United States' right to expand its boundaries to the Pacific. In 1846, the conflict with Mexico became a war. By winning the war, the United States gained California and the rest of the Southwest.

In 1848 the discovery of gold brought thousands to California who hoped to find quick riches. Those who arrived in 1849 were called “forty-niners.“ By 1850 California was ready to apply for statehood. In the Utah Territory a religious group settled near the Great Salt Lake. Led by Joseph Smith and later by Brigham Young, Mormons made the journey west to escape religious persecution.