Source : Webster's Revised Unabridged Dictionary (1913)

Peacock Throne \Pea"cock` Throne\
   1. A famous throne formerly of the kings of Delhi, India, but
      since 1739, when it was carried off by Nadir Shah, held by
      the shahs of Persia (later Iran); -- so called from its
      bearing a fully expanded peacock's tail done in gems.