To the units of the left wing that would wheel through Switzerland, all of which were composed exclusively of Austrian troops, Schwarzenberg issued the following proclamation from his headquarters at Lörrach on 21 December:

“Soldiers!” We enter Swiss territory as friends and liberators. Your conduct must be appropriate for this role. Show the Swiss how Austria's warriors are no less familiar with the duties that are expected of them during the passage through a friendly land and the careful treatment of the inhabitants as they are with the qualities that lead them to renown and victory on the day of battle. If the course of the war makes it necessary to expose you to arduous marches and exertions in the inclement time of year, forget not, soldiers, that it now depends on completing laudably what you have laudably started, that far greater difficulties and dangers than those which you will still encounter already have been defeated, and that from your bravery and steadfastness your Fatherland and the world expects a speedy, honorable and lasting peace.

Despite Schwarzenberg's trepidation, the Basel operation proceeded smoothly. The Swiss withdrew their artillery from the Basel bridge during the night of 20–21 December. Swiss forces evacuated the city early on Tuesday, the 21st, without offering any resistance and leaving the bridge intact. At 8:00 A.M. Austrian troops occupied Basel's St. Paul suburb and gate.