There are records of a Samuel O'Shields born ca. 1799 in South Carolina and living in Spartanburg SC until the 1840 census. There is another Samuel O'Shields born ca. 1842 in South Carolina and living in Georgia in 1860. I find no records, civil or military, of anyone else by that name from this period of time. Do you have evidence that this person named in your post actually lived in 1860 or later?