Columbus Delano represented Ohio districts in Congress, 1845-47 and 1865-69, before being appointed Commissioner of Internal Revenue. In 1870, he became Secretary of the Interior. These letterpress copy books document his work at the Bureau of Internal Revenue through his third year as Secretary of the Interior. A large number of the letters deal with appointments and patronage, with a few concerning Native American affairs.
The letterbooks came to the Library in 1916, through the assistance of Dean David Kinley.