Proto Monster Manual (1957)

I've often wondered about the seemingly haphazard collection of monsters in the early D&D Monster Manuals. Certainly some creatures are easy to figure out why they were included, like the Otyugh or the Troll, but others really left me puzzled. Why Catoblepas AND Leucrocotta AND Brownies and so on? Why this set of mythological creatures that were sometimes well known and other times things so obscure I thought them original creations for the game?

It seems that the name of the book was the biggest clue: The Monster Manual.  In 1957 Jorge Luis Borges wrote a book in Spanish called Manual de zoología fantástica. This was updated (and translated) during the 1960s and eventually included 120 different mythical beasts from folklore and mythology.

This included:

• Basilisk
• Brownies 
• Catoblepas
• Centaur
• Chimera
• Leucrocotta
• Dopplegänger
• Gnomes
• Golem
• Griffin
• Harpies
• Hippogriff
• Hydra
• Jinn
• Lamia
• Lemuri
• Manticore
• Minotaur
• Nāga
• Nymphs
• Merman
• One-Eyed Beings (?)
• Peryton
• Roperite (!)
• Salamander
• Satyrs
• Scylla
• Sea Horse
• Sirens
• Sphinx
• Sylph
• Troll
• Unicorn

I don't know about you... but I think it's safe to say Manual de zoología fantástica was the proto Monster Manual. More interesting is the monsters left behind and waiting for inclusion in a future Manual de Monstruos!