I believe in a form of collective unconscious but I relate it
  more to "things in common" simply by being human. Our societies
  are all similar. Our needs are all similar. Our hopes and dreams
  are all similar. But we use different types of symbolism to
  express difficult concepts with depending upon our cultures,
  which is why different cultures use different types of
  symbolism. Egypt has its set of symbolisms. Christian cultures
  (the West is a Christian culture steeped in Christian symbolism)
  have theirs, Chinese culture has theirs, Japanese culture has
  theirs.

  They can all be tied together of course; the specifics differ
  but the underlying concepts are more-or-less similar.

  Is it a collective unconsciousness? Of a sort, yes.*

  We can even level up to Gaia; from a long-away perspective, we
  could be considered "one life form" on this planet. Like a slime
  mold oozing over the planet over billions of years, dependent
  upon the systems of this planet for birth, life, death,
  reconstruction, rebirth and continuation into myriad
  metaphorphized forms.

  In that sense, all life is one and connected, and it's not
  unreasonable that being similarly patterned as humans that we
  would have similar unconsciousnesses.

  Is there a deeper connection? Quite possibly.*

  I'm a fan of embodied cognition and with that, the brain, the
  body and the environment and our social relationships are all
  "one thing", like a machinery with invisible wires that we just
  can't see or measure at present using scientific tools, but
  we're certainly aware of in day-to-day life via communication,
  feelings, words, etc.

  Even here; are you an I physically connected in some way?

  Absolutely. My brain and yours are linked across the gaps of
  Time as we negotiate meaning as we communicate.

  So it's not unreasonable to me to consider a collective
  unconsciousness as being a tangible reality.