He engineered a coup in November 1799 and became "First Consul of the Republic". Intractable differences with the British meant that the French were facing the War of the Third Coalition by 1805. Napoleon shattered this coalition with decisive victories in the Ulm Campaign, and a historic triumph at the Battle of Austerlitz, which led to the dissolving of the Holy Roman Empire. In 1806, the Fourth Coalition took up arms against him because Prussia became worried about growing French influence on the continent. Napoleon quickly knocked out Prussia at the battles of Jena and Auerstedt, then marched the Grande Armée deep into Eastern Europe, annihilating the Russians in June 1807 at Friedland, and forcing the defeated nations of the Fourth Coalition to accept the Treaties of Tilsit. Two years later, the Austrians challenged the French again during the War of the Fifth Coalition, but Napoleon solidified his grip over Europe after triumphing at the Battle of Wagram.