The Bigelow-Monks correspondence contains correspondence from several soldiers serving in the Union Army during the Civil War, as well as a series of letters written by Charles A. Monks to his wife Susannah, when he was in Gibbon, Nebraska. Much of the collection consists of the war-era correspondence of several soldiers to Susannah Bigelow and to the Monks family, from friends and family members. Several of Susannah's friends wrote throughout the war, and described in detail their experiences in camp, on the battlefield, and in the hospital. Corporal Jeremiah P. Williams of the 57th New York Infantry Regiment wrote early of his optimism for the Union effort; he drew a patriotic picture of an eagle holding the shield of the United States in his letter of January 23, 1862; he also discussed his impressions of the battle site of First Bull Run at Manassas, Virginia. Lewis Turner, a soldier in the 15th New Jersey Infantry Regiment, served with Charles A. Monks in Company C, and frequently told Susannah of his experiences, including a detailed description of the Battle of Fredericksburg (May 28, 1863). Turner was wounded in the Spotsylvania campaign, but later returned to his regiment. Beverly Post of the 7th New York Heavy Artillery Regiment became a frequent correspondent later in the war, as did his brother Jerry, who often discussed his experiences recuperating from a wound at Stanton Hospital in Washington, D. C. The Posts often referred to Susannah's brother Jonathan, and alluded to his status as a prisoner of war in early 1865.
The collection holds a large number of items written by Charles A. and Sidney N. Monks to their sister Jarrett and to their father William. The pair described the details of camp life during the defense of Washington, D. C., early in the war, but their later correspondence reflects their increasing involvement in the fighting; Charles wrote at one point that he was lucky to have only a bullet through his clothing. Both brothers detailed their battlefield experiences, and both participated in the Battle of Gettysburg. Sidney mentioned enclosing a ring taken from a dead Confederate soldier in his letter of August 15, 1863, and Charles twice provided detailed descriptions of the fighting, in his letters of July 6, 1863, and July 17, 1863. In the second letter, he drew a small map of the Confederate lines. Each of the soldiers provided a rich view of army life, and several wrote on illustrated Union stationery.
A series of letters from 1871 pertains to the experiences of Charles A. Monks as he headed to Gibbon, Nebraska, to assess the possibility of starting a farm there under the Homestead Act. In his letters to his wife Susannah, who remained in New Jersey, he provided detailed descriptions of people, scenery, and everyday life out west. He liked his neighbors and Nebraska, but he returned to his New Jersey home in October 1871.