Society of the Cumberland :

 Report of the First Meeting of the Society - 1868
tells of
Rosecrans naming Army of the Cumberland

 from Internet Achives

General Rosecrans was unable to attend this first meeting but sent a letter encouraging them in the efforts and expressing his regrets for not attending.
Return to Rosecrans, Part 4, Civil War
Return to Rosecrans, Part 5
Post War Life