Central Intelligence Agency
Cia: Intelligence in the Civil War [Pdf]
A multi-topic look at intelligence gathering, the tools used, and the people involved in both the North and the South during the Civil War. Comprehensive, interesting coverage from the CIA.
Harp Week
The End of Slavery: The Creation of the 13th Amendment
What a wonderful resource for researching the attempts to solve the issue of slavery prior to the Civil War, and the eventual ratification of the 13th Amendment. Find a timeline of legislation limiting the spread of slavery from 1787...
Other
West Virginia in the Civil War: The Jessie Scouts
A thorough discussion of the formation and use of the Jessie scouts who were mainly cavalrymen who gathered intelligence. Dressed as Confederate soldiers, they were used extensively by General Sheridan in the Shenandoah Campaign.
Other
Californians and the Military: John Charles Fremont and the Bear Flag Revolt
A brief retelling of John C. Fremont's expedition to California. Learn about his confrontation with Mexican authorities that led to the Bear Flag Revolt.
American Battlefield Trust
American Battlefield Trust: Civil War Biography: John C. Fremont
A profile of John Fremont makes note of his short stint as a the Union army officer.
Independence Hall Association
U.s. History: The Mexican American War
The Mexican-American War fulfilled James Polk's desire to acquire the territory of New Mexico and California from Mexico. See how the fight was provoked, and read about Stephen Kearny's actions in New Mexico and John Fremont's in...
Museum of the City of San Francisco
Virtual Museum of San Francisco: William T. Sherman and Early California History
From the memoirs of William Tecumseh Sherman you can read about his arrival in California during the Mexican War, his dealings with John Fremont, and the Bear Flag Revolt.