Maybe this has been a phenomenon you've run into, maybe not. I have had one heck of a time finding many of my southern ancestors, especially the direct line, in the 1870 census. I do run into a few from collateral lines, but it seems that especially the ones that I know actually fought in the War can't be found in the 1870 Census. I can find them in the 1880, so they didn't die or move. It almost seems as if they hid from the census taker!
I've actually gone as far as to visually scan each page of the census for the entire county or parish in which they were known to have lived at the time, in case it was just a matter of transcription or indexing error, but no luck!
Anyone else find this when looking for their Confederate soldier/family?