

In correspondence he noted that many of the original publishing plates used to reproduce his work were not available though the original works were thought to survive. Spier reserved all rights and retained the copyrights to his works. Close examination will often yield a humorous scene not readily apparent at first glance the finding of which often delights readers of all ages. Many of Spier's illustrations are extremely detailed and historically accurate. Like other children's illustrators such as Beatrix Potter or Christopher Wormell, Peter Spier demonstrates his talent and skills as an artist/illustrator using pen, ink and watercolour on paper. He died on Apin Port Jefferson, New York.

Spier started his career as a commercial artist for advertising agencies and only later focused on writing and illustrating children's books.

The entire Spier family emigrated to the United States in 1950. After the war he studied at the Rijksakademie in Amsterdam and joined the Royal Netherlands Navy for four years. Jo Spier was Jewish, and, during the Second World War, Peter and his father were two of nine prisoners of Villa Bouchina and were later imprisoned in Theresienstadt. Spier was born in Amsterdam, North Holland, and grew up in Broek in Waterland, the son of Jo Spier, a popular artist and illustrator, and Tineke van Raalte.
