The 21st US Infantry didn't exist during the Civil War, so this is either post-Civil War (it was re-established after the Civil War, in 1866, so it might be garrison duty) or possibly (not likely) a mistake of some sort.
No matter, it's a great cover; now let's see if we can place your lt Riley
From wt1, on scf. This guy can track everyone!
http://www.stampcommunity.org/topic.asp?TOPIC_ID=34135
The stamp appears to be Scott 94 (3c red F grill) which had an EDU of March 21, 1868 per my 2011 catalog.
The 21st Infantry was constituted as 2nd Battalion, 12th Infantry on May 3, 1861. The unit was redesignated as 21st Infantry on December 7, 1866.
The lineage and honors of the 21st Infantry can be viewed here.
re: Civil War Cover to a Soldier
The 21st US Infantry didn't exist during the Civil War, so this is either post-Civil War (it was re-established after the Civil War, in 1866, so it might be garrison duty) or possibly (not likely) a mistake of some sort.
No matter, it's a great cover; now let's see if we can place your lt Riley
re: Civil War Cover to a Soldier
From wt1, on scf. This guy can track everyone!
http://www.stampcommunity.org/topic.asp?TOPIC_ID=34135
re: Civil War Cover to a Soldier
The stamp appears to be Scott 94 (3c red F grill) which had an EDU of March 21, 1868 per my 2011 catalog.
The 21st Infantry was constituted as 2nd Battalion, 12th Infantry on May 3, 1861. The unit was redesignated as 21st Infantry on December 7, 1866.
The lineage and honors of the 21st Infantry can be viewed here.