By 1806, Hinrichs was a General-major in command of a brigade in Eugene Frederick Henry, Duke of Württemberg's Prussian Reserve in the War of the Fourth Coalition. On 17 October 1806, he fought in the Battle of Halle against the French I Corps under France Jean-Baptiste Bernadotte. Hinrichs' Advance Guard was made up of the Borell Fusilier battalion Nr. 9, Knorr Fusilier battalion Nr. 12, and Hinrichs Fusilier battalion Nr. 17, two squadrons of Usedom Hussar Regiment Nr. 10, one squadron of Hertzberg Dragoon Regiment Nr. 9, one squadron of Heyking Dragoon Regiment Nr. 10, and two horse artillery pieces.[4]