Having completed all the arrangements, on June 26th the main body of this expedition had moved from the fort; and after a rapid but interesting march of eight hundred seventy-three miles, on August 18th it entered and took possession of Santa Fe, the capital of New Mexico, the Mexican forces, numbering four thousand, which had been collected to defend the town, having dispersed, without offering the least opposition, as it approached.

While these operations in New Mexico and on the western frontier of the United States were taking place, Brevet-Captain John C. Fremont, who had been engaged in explorations on the western slope of the Rocky Mountains, had also revolutionized the Province of California, and, to some extent at least, had anticipated the movements of the expedition commanded by General Kearney.  The character of his mission being scientific and peaceful rather than warlike, he had not had an officer or soldier of the regular army in his company; and his whole force had consisted of sixty-two men employed by himself for security against the Indians and for procuring subsistence in the wilderness and desert country through which he had passed.  For the purpose of obtaining game for his men and grass for his horses, in an uninhabited part of California, he had, during the winter of 1845-1846, solicited and obtained permission from the Mexican authorities to winter in the Valley of San Joaquin; but he had scarcely established himself before he received advices that the Mexican commander was preparing to attack him under the pretext that under the cover of a scientific mission he was exciting the American settlers in that vicinity to revolt.

In view of this threatened attack, and for the purpose of repelling it, Lieutenant Fremont immediately occupied a mountain which overlooked Monterey—­although it was thirty miles from that city—­and having intrenched it and raised the flag of the United States he waited the approach of the enemy.  After remaining there until March 10, 1846, he retired to the northward, intending to march, by way of Oregon, to the United States; but about the middle of May, after he had quietly passed into Oregon, he had received information through Samuel Neal and Levi Sigler, two hunters who had been sent after him from Lassen’s rancho, that the Mexican Governor of California was pursuing him, while the Indians, by whom he was surrounded, instigated by the enemy, had shown signs of hostility, and had killed or wounded five of his men.

Under these circumstances, on June 6, 1846, Lieutenant Fremont had resolved to turn on his pursuers with the little party under his command, and to seek safety, not merely in the overthrow of his pursuers, but in that of the entire Government of Mexico in the Province of California.  Accordingly, on June 11th, Lieutenant Fremont, assisted by Captain Merritt and fourteen of the settlers, had attacked and captured an escort of horses destined for General Castro’s troops—­Lieutenant