Richard -- Re Child #4. Lady Isabel & the Elf Knight, aka The Outlandish Knight

--'The lady of the title is named variously as "Lady Isabel", "the King's daughter" "May Collin", "May Colven", "pretty Polly", or not named at all. Variants of the song usually imply that she is rich and beautiful. The knight is, in some versions, a normal, but villainous, mortal man, but in others he is an "elf knight".' Wikipedia--

"Pretty Polly", whose lover rides off with her & tells her that he "dug on her grave the best part of last night", is surely related, Richard - as the inclusion of the name above suggests was agreed by the writer of the Wiki article. "Lady Isabel", Child #4, has indeed its own entry at Roud 21; but Pretty Polly still seems to me to be related in the theme of the lover who lures the woman away, meaning to murder her.

Here is the entry in Roud's index:-

--15 "The Cruel Ship's Carpenter" ("The Gosport Tragedy"; "Pretty Polly") (Laws P36A/B)--

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