The Judeo-Masonic conspiracy is an antisemitic and anti-Masonic conspiracy theory involving an alleged secret coalition of Jews and Freemasons. Antisemitism blended after the French Revolution with anti-philosophe, anti-Masonic and anti-Illuminati conspiracy theories, particularly upon the dissemination of the Simonini letter by Augustin Barruel in 1806 and so the idea of the influence of Masons under Jewish domination found a fertile ground among diverse European authors throughout the 19th century. These theories are popular on the far-right, with similar allegations still being published.