I have tried for several years to find my great grandfather's war record.His name is John Allen Campbell.He lived in Franklin County, Arkansas. I have written to the National Archives in Washington and several other military records places and they say they have no record of him. Enrolled August 1, 1863. Invalid pension application 1890. Widow pension application 1918. Wife, Margaret Elizabeth Blackwell. John was born in Perry County, Tennessee.He was a Pvt in Co. E., 4th Arkansas Union Calvary. Age 24. Enlisted at Cassville. Any ideas on how I could find his military record? I would appreciate any help. Thanks!