When the Convention met the military situation was undergoing an extraordinary transformation that seemed to confirm the Girondin prophecies of easy victory. After Valmy, the Prussians withdrew to the frontier, and in November, French troops occupied the left bank of the Rhine. The Austrians, who had besieged Lille in October, were defeated by Dumouriez at the Battle of Jemappes on 6 November and evacuated the Austrian Netherlands. Nice was occupied and Savoy proclaimed its union with France. The successes made it safe to quarrel at home.