Letters and manuscripts relating to the political activities of Ortega and his allies in the United States. These activities include his efforts to purchase weapons and military supplies for the Mexican army, recruit citizens of the United States and other countries to fight in Mexico, raise funds for the war with France and build railroads and telegraph lines in Mexico. Many letters also discuss the effort by Juárez to remove him from power and Ortega's arrest by the US government in 1866. Others pertain to efforts by Ortega's political allies to show support for the Mexican Liberal cause.