Webster 1913 Edition
Webster 1828 Edition
THEMSELVES, a compound of them and selves, and added to they by way of emphasis or pointed distinction. Thus we say, they themselves have done the mischief; they cannot blame others. In this case, themselves is in the nominative case, and maybe considered as an emphatical pronoun.
In some cases, themselves is used without they, and strands as the only nominative to the following verb. Themselves have done the mischief.
This word is used also in the objective case after a verb or preposition. Things in themselves innocent, may under certain circumstances cease to be so.
They open to themselves at length the way.