noun earlier than 1960
The tribal practice of decapitating enemies and preserving their heads gave us the first sense of headhunter around 1800. Nowadays we’re more likely to think of the less gruesome recruitment practice of targeting highly skilled or experienced personnel. The evidence suggests that this sense emerged in the United States, where our first example of headhunter, in 1960, comes from:
1960 Harold Wentworth & Stuart Berg Flexner Dictionary of American Slang 248/2
The executive type of headhunter was surely active prior to the word appearing in this slang dictionary. Can you find any earlier examples?
From an article called "The Secret Mines of Russia's Germany" in Life Magazine of September 25, 1950:
I think I've found a 1946, in a US radio discussion transcript. I found it in a snippet via Google Books, and I couldn't find a full version available online to confirm, but have excavated some extra info that makes the year seem plausible.
Here's the quote:
It's from Northwestern University on the Air, the Reviewing Stand, Volume 7, published by Northwestern University Radio Department, 1946.
It's a radio discussion with: "Speakers: E. E. Scannell; Don Sandoval; James H. McBurnley; Moderator: A. J. Hamman; Phillip Smith."
(Here's a link to Northwestern University Library if you want to check with them.)
The current earliest dating in the OED for the original head-as-a-trophy meaning is 1853. For good measure, here's an April 1800 example from a "Description of the Island of Borneo" by Mr. Von Wurmb in The Philosophical Magazine: