Where are Leonardo's canvas oil paintings he described? This report analyzes the historical and scientific details of a powerful, large painting bought at auction in France. Carbon-14 dates the canvas to around 1460s and the painting to 1514, the time Leonardo was in Rome. It encapsulates the geopolitical strategy of Medici Pope Leo X to create an alliance with France and stop the early church reform. It shows striking improvements to the Milan 'Last Supper' incorporating a mathematical structure, the only painted self-portrait of Leonardo and a replacement of the 'Christ' figure by Julian, the brother of Pope Leo X, who married into the French royal family of Francis I. This great work captures the turning point to the modern era, freedom of thought, religious and political emancipation from the tyranny of the sword and superstition. X-ray photography reveals Leonardo signaled his initials on his final masterpiece, not once with his hands, nor twice but three times.