See: https://www.genealogy.com/ftm/b/r/o/Melissa-M-Brown-DANVILLE/WEBSITE-0001/UHP-0018.html

Family reports on Geni that his Indian name was Birdtail Doublehead, his father was Chief Doublehead, his Grandfather, Chief Grey Eagle.

Family lore is pretty consistent that he died of fever after Shiloh.

However Cherokee Geneology here https://www.wikitree.com/wiki/Doublehead-7
indicates a death in 1857 and his son in a Eastern Cherokee Nation application for funds in 1907 indicates a 1860 death.

So we have a DOB ranging from 1795 to 1817. In any case he was old for the Civil War and the 1857 date seems pretty solid. Of course this all assumes James Lee Mason was one and the same Birdtail Doublehead which I have some suspision about.

JJR