Lange Pier misquotes William Shakespeare's "The Life and Death of Richard the Third" Act 5, Scene 4 when he says "My horse! A kingdom for my horse!"
This story is not based on any episode from Floris (1969), but was written by Gerard Soeteman as an audio play (performed by the original actors from the Dutch TV series) that was released on side one of a record titled "Floris en de Fakir". It was also adapted into a newspaper strip by Gerrit Stapel in 1973.