In the notes to Book II of the Social Contract, Rousseau remarks:
"The Republic of Thiascala, enclosed by the Mexican Empire, preferred doing without salt to buying from the Mexicans, or even getting it from them as a gift. The Thiascalans were wise enough to see the snare hidden under such liberality. They kept their freedom, and that little State, shut up in that great Empire, was finally the instrument of its ruin."
I've googled Thiascala, but have come up with nothing (ie all results were references to his book). Is it a figment of his imagination? A parable to illustrate his theory?