The Royalist plan of campaign was this: They reckoned the energy of the Revolution so low that they counted pretty confidently, in the summer of 1792, on the ability of their party to defend the Tuileries against any force which could be brought against it; but assuming that the Tuileries could not be defended, and that the King and Queen should be massacred, they believed that their own position would be improved. Their monarchical allies would be thereby violently stimulated. It was determined, therefore, that, regardless of consequences to their friends, the invading army should cross the border into Lorraine and, marching by way of Sierk and Rodemach, occupy Châlons. Their entry into Châlons, which they were confident could not be held against them, because of the feeling throughout the country, was to be the signal for the rising in Vendée and Brittany which should sweep down upon Paris from the rear and make the capital untenable. At Châlons the allies would be but ninety miles from Paris, and then nothing would remain but vengeance, and vengeance the more complete the greater the crime had been. All went well with them up to Valmy. The German advance on August 11, 1792, reached Rodemach, and on August 19, the bulk of the Prussian army crossed the frontier at Rédagne. On August 20, 1792, Longwy was invested and in three days capitulated. In the camp of the Comte d'Artois "there was not one of us," wrote Las Casas, "who did not see himself, in a fortnight, triumphant, in his own home, surrounded by his humbled and submissive vassals." At length from their bivouacs at Saint-Remy and at Suippes the nobles saw in the distance the towers of Châlons. The panic at Châlons was so great that orders were given to cut the bridge across the Marne, but it was not until about September 2, that the whole peril was understood at Paris. It is true that for several weeks the government had been aware that the West was agitated and that Rouërie was probably conspiring among the Royalists and nonjuring priests, but they did not appreciate the imminence of the danger. On September 3, at latest, Danton certainly heard the details of the plot from a spy, and it was then, while others quailed, that he incited Paris to audacity. This was Danton's culmination.