Gargarenses

In Greek mythology, the Gargareans (or Gargarenses) were an all-male tribe. They had sex with the Amazons annually in order to keep both tribes reproductive. Varying accounts suggest that they may have been kidnapped, raped, and murdered for this purpose, or that they may have had relations willingly. The Amazons kept the female babies they produced and raised them as warriors and gave the males to the Gargareans.
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[Greek heroic] A mythical people that existed only of men. Each year the amazons would associate with them in order to secure their existence.