I’m rather proud of figuring this one out, because I really hadn’t a clue as to why this Fish Bar would be such a bad idea. Then it occurred to me to look up the word ‘Dagon’. Webster’s doesn’t have it, but luckily Brewer saves the day, as usual: ‘Dagon’ is the Hebrew name for the god Atergata of the Philistines; half woman and half fish.
It was actually a Dagon temple that the biblical Samson managed to push down in his final effort to annoy the Philistenes (Judges 16:23, “Then the lords of the Philistines gathered them together for to offer a great sacrifice unto Dagon their god, and to rejoice: for they said, Our god hath delivered Samson our enemy into our hand.”)
After including this annotation in earlier editions of the APF, there have been numerous emails from people pointing out that H. P. Lovecraft also uses the entity Father Dagon as the leader of the Deep Ones in some of his horror stories. Terry has confirmed, however, that the inspiration for his Dagon goes back to the original source, not Lovecraft’s incarnation.