The five dollar bill you see below is the design type used for series of 1890 and series of 1891 five dollar treasury notes. The man with the beard is George Thomas. He was a Union General during the Civil War. Generally speaking, $5 treasury notes from 1890 are much rarer than the similar designed bills from 1891. 1890 notes have a back that is mostly green. 1891 examples have a back that has a lot more white. Both notes are equally collectible, but neither is as popular as it could be.
