The Correspondence series forms the bulk of the collection and is comprised of letters written by Alfred G. and John E. Ryder from August 1861 to July 1863 during their time of service in the Civil War. It is a rich series, as the letters are highly descriptive of their surroundings and living conditions, as well as of their feelings about what is happening to them and to their friends. A number of their letters are addressed to "Dear Friends" and a few are written to each other, "Dear Brother"; the majority are to family members at home: Father, Mother and Sister (Elizabeth, or Ibby, then about age 16). In the Miscellaneous folder are letters from friends and officers, most following the deaths of the brothers at Gettysburg in July 1863. Several letters from John G. Frey at Gettysburg describe the arrangements he made for exhuming the bodies, the specially sealed coffins and shipping, as well as requests for payment. Two letters are from Henry Hoisington to George Ryder; he was in the 24th with John and included the letters when John wrote to his father. There are also two letters written in 1864 from Alfred Fay (2nd Michigan Cavalry, Co. B) to his wife. There are three folders of handwritten Transcripts of the letters, which were prepared by family members. The Correspondence and Transcripts series are both arranged chronologically by the brother who wrote them.
In the late 1930s Raymond A. Ryder, Sr., son of Charles and nephew to John and Alfred, divided the Civil War letters and mounted them into three letterbooks along with brief notations he made about the contents of the letters. These letterbooks were distributed to family members. His own letterbook of original letters was eventually donated to the Bentley Historical Library; photocopies of the other two books were made available by Ryder family descendants. The letters were coded in the order they appeared in each of the three volumes (LB-#, BG-# and JK-#), and are filed chronologically in the Correspondence series. The notations are filed by volume in the Letterbooks series.
