In the initial posting about the territories which constituted the Kingdom of Westphalia (Brunswick, Hanover, Hesse-Kassel), Prussia was forgotten (the parts on the left bank of the Elbe plus a fortress rayon on the right bank fo the Elbe, vis-à-vis of Magdeburg). By that the former Prussian cities Magdeburg and Halle became parts of Westphalia.
The cheering of the citizens was great, when the Prussian troops came back to Halle (in the spring and autumn campaign 1813), according to several eyewitness memoirs (e.g. of the Freiwilligen Jäger / volunteers Dultz and v. Rauchhaupt), so it looks, that the citizens preferred the Prussian rule over the Westphalian .
Best regards, Thomas