Accordingly, leaving Field Marshal Count Kurt von Schwerin in Silesia with 25,000 soldiers to guard against incursions from Moravia and Hungary, and leaving Field Marshal Hans von Lehwaldt in East Prussia to guard against Russian invasion from the east, Frederick set off with his army for Saxony. The Prussian army marched in three columns. On the right was a column of about 15,000 men under the command of Prince Ferdinand of Brunswick. On the left was a column of 18,000 men under the command of the Duke of Brunswick-Bevern. In the centre was Frederick II, himself with Field Marshal James Keith commanding a corps of 30,000 troops. Ferdinand of Brunswick was to close in on the town of Chemnitz. The Duke of Brunswick-Bevern was to traverse Lusatia to close in on Bautzen. Meanwhile, Frederick and Keith would make for Dresden.

The Saxon and Austrian armies were unprepared, and their forces were scattered. Frederick occupied Dresden with little or no opposition from the Saxons. At the Battle of Lobositz on 1 October 1756, Frederick stumbled into one of the embarrassments of his career. Severely underestimating a reformed Austrian army under General Maximilian Ulysses Browne, he found himself outmanoeuvred and outgunned, and at one point in the confusion even ordered his troops to fire on retreating Prussian cavalry. Frederick actually fled the field of battle, leaving Field Marshall Keith in command. Browne, however, also left the field, in a vain attempt to meet up with an isolated Saxon army holed up in the fortress at Pirna. As the Prussians technically remained in control of the field of battle, Frederick, in a masterful coverup, claimed Lobositz as a Prussian victory.