Hi, Donuel -- In both Scotland and Ireland, Himself (or Herself) is the person of greatest significance in the household, family or clan. The usage is an early modern (i.e., 17th-18th-century) English-language rendering of a Gaelic phrase that translates literally as "him, that one". In my opinion, the best 21st-century translation is "You Know Who", complete with initial caps.

I use it to refer to my husband on Facebook, of which he is not a member, in order to defend his last shreds of Internet privacy. I have noted, however, that he is pleased when I photograph him doing interesting things and post the pics on Facebook ...

Ah, well. What's that line about too great a concern for consistency being the hobgoblin of little minds?