Arthur Balfour was born on July 25, 1848 and died on March 19, 1930. Arthur Balfour would have been 81 years old at the time of death or 163 years old today.
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Though we know the estimated date of death (537 at the Battle of Camlann), we don't know when he was born. Of course this is all assuming he ever actually existed. -~Iolaos~-