Comments:

Frederick Rixinger was a soldier from Company I of the 1st Infantry Regiment.  At some time prior to his death Rixinger would have been convicted by court marshal of some military offense and sentenced to the prison on Alcatraz, where he died.  The lack of a cross or other emblem on his tombstone reflects his inmate status.  Army inmates on Alcatraz were designated either as "military convicts" or "general prisoners."  Military convicts  had been dishonorably discharged and were spending the rest of their enlistment periods (or longer, if the offense was serious enough) in confinement. General prisoners like Rixinger, however, were sentenced to Alcatraz for a period of time, but after that had been served they would be returned to their units and allowed to serve the rest of their enlistment.

The 1st Infantry had been created back in 1784.  In 1886 the regiment was sent to California, and its companies garrisoned both Angel Island and Alcatraz.