There seem to be several different branches of Swiss Infangers in the United States.  All originating in either the Bern, Uri or Obwalden cantons.

The earliest Infanger arrival to the US, that I know of, was Josef Infanger and he emigrated about 1862 from an unknown village in Switzerland to the US.  He enlisted into the Union Army on Jul 22, 1863 in Company G, 15th Heavy Artillery Regiment, New York, which was formed in Virginia. After the Civil War, he moved to St Louis Co, Missouri and married. His descendants have mostly stayed in Missouri.  Josef Infanger's name was anglicized to Joseph Feiner during the Civil War, per pension affidavits, as it was too difficult to pronounce.

The next arrival was a couple, Charles Infanger and Catherine Imhof, from Uri canton, immigrating to New York in 1880. The descendants of this couple have remained primarily in the Northeast.  Charles' brothers, Johann & Christian imigrated about 1889. Please see below Nick Cardello's terrific website on the Uri canton Infangers.

The third known branch was from the Engelberg, Obwald canton.  Brothers, Joseph and John, immigrated about 1881 to Colorado and their descendants are mostly in Colorado and Idaho.

Thank you to everyone who shares their genealogical information. Please feel free to send corrections.  And because in the beginning I was ignorant, I didn't keep track of sources as I should have, so please let me know if you should be credited.