Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) said: When this verse was revealed: "And do not eat of that upon which the name of Allah has not been mentioned" [Surah al-An'am: 121], Persia sent a message to Quraysh: Dispute with Muhammad (peace and blessings be upon him) and say to him: What you slaughter with your own hand with a knife is lawful, yet what Allah has slaughtered with a sword of gold (that is, what dies by itself) is unlawful? Thereupon this verse was revealed: "And indeed the devils inspire their allies to dispute with you" [Surah al-An'am: 121]. He said: "The devils are (the people) of Persia, and their allies are from Quraysh."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 11564